Re: [Repeater-Builder] Re: no power out of duplexer SOLVED with more questions
John, here's a more subtle lesson on repeaters, and it has nothing to do with hardware... If you dial the power back 1 dB, your PA may be much happier. If you simultaneously change the courtesy beep to be 10% faster, users will ask you what's changed on the repeater. Tell them you've increased the transmitter output 3 dB, and they'll claim to have noticed the improved coverage. Tell him guys...am I wrong? ;^) 73, Paul, AE4KR - Original Message - From: Tim Sawyer To: Repeater-Builder@yahoogroups.com Sent: Monday, September 06, 2010 2:43 PM Subject: Re: [Repeater-Builder] Re: no power out of duplexer SOLVED with more questions In that spirit. Going from 80 to 100 watts is 0.97 db better. That's probably not an improvement your users will notice. When one considers what a pain it is when the PA dies, it might not be worth it. Just my 2 cents but I think you're better off leaving the amp at 80 watts.
Re: [Repeater-Builder] Interference on VHF repeater
Brett, How did you determine it's an IM product? What repeater/controller combination are you using? I'd try powering down the controller and manually keying the transmitter. If that solves it, it could be the controller's reference oscillator or divider outputs leaking onto the PTT line or elsewhere. Any compact fluorescent lights nearby? 73, Paul, AE4KR - Original Message - From: brett To: Repeater-Builder@yahoogroups.com Sent: Saturday, September 04, 2010 5:26 AM Subject: [Repeater-Builder] Interference on VHF repeater I have the distinctive hollow pipe sound. Both TX and RX have the same CTCSS tone. The intermod product is however not always present, and after looking at the RX output from the duplexer with a SA I see a comb of products that move slowly in time. When one of the products in the comb falls within the RX bandwidth the RX opens, until it moves on. This is not a busy site, and I have been able to power down everything on site except my repeater. Problem remains unchanged.
Re: [Repeater-Builder] Re: Circular polarization for VHF repeaters?
Gordon, something worth trying might be low-band. About 20 years ago, I lived in an area where hams did course communications for rally events in very mountainous terrain. I remember experimenting one night about 2am with my partner at the other end of a heavily wooded course, about 12 miles end-to-end. 444 MHz simplex, 5 watts, colinear mobile whip - no copy. 146 MHz simplex, 5 watts, 5/8-wave mobile whip - no copy, but would barely break the carrier squelch. 29.6 MHz simplex, 4 watts, FM CB conversion, 1.3m helically-wound mobile whip - full quieting and S9+. Antennas might be a bit of a trick for portables on 10m, and a repeater might have to be crossband, but worth a shot. 73, Paul, AE4KR - Original Message - From: Gordon Cooper To: Repeater-Builder@yahoogroups.com Sent: Thursday, September 02, 2010 1:51 AM Subject: Re: [Repeater-Builder] Re: Circular polarization for VHF repeaters? Our repeater runs 5 watts output, needs to run three or four days off a gelcell, and most importantly has to fit into a backpack to be carried to a convenient hilltop. Fortunately, the split is 3 MHz so that the duplexer is of a reasonable size. The problem is getting reasonable coverage. Sure the search areas are fairly small but usually encompass several ridges and deep valleys. We use vertical polarisation with a 5/8 whip on the repeater and the search teams have flexible dipoles that fit into their backpacks. Sharp ridges and steep slopes contribute to coverage problems. Would circular polarization help?? I think not.
Re: [Repeater-Builder] Duplexers
Don, this is a natural response, or lack thereof. If you ask, will I have this problem, and nobody else has had it, that doesn't mean they can guarantee YOU won't have it, so they refrain from commenting. I learned a lot from my experience with one outdoor, rooftop repeater I built. I was expecting condensation in places where I could find no evidence of it actually occurring. It finally dawned on me that even if the ambient humidity is 100%, and condensation is collecting on the outside of the cabinet, the equipment inside is safe as long as the temp there remains even slightly above the outside. If you have to mount the duplexers away from the transmitter and power supply, condensation may be more difficult to control. Whenever possible, I will always try to keep the cans (and all the equipment) slightly warmer than outside ambient. I believe that in most installations, even in non-climate-controlled buildings, this is likely to happen by default, especially if you are co-sited with lots of other people's stuff. On my rooftop repeater, I ended up using a completely sealed, gasketed steel cabinet, painted a light color, with no vents to the outside whatsoever, and relied on plain old heat loss through the cabinet walls for dissipation. When I changed out my 2-watt, solar-powered, Repco UHF repeater for a 35-watt, converted GE Mastr II powered from the AC mains, I expected problems, so I put a 119ºF attic fan switch on the transmitter's heatsink, wired to a logic input on the controller. It never triggered, even in the summer, and this was in orlando, FL. The commercial stuff is based on components which were designed to stay happy for years locked in a car trunk. It may be possible to overdo ventilation. I think I'd rather err on the side of staying a little warm in a repeater shack, within reason. 73, Paul, AE4KR - Original Message - From: ka9qjg To: Repeater-Builder@yahoogroups.com Sent: Tuesday, August 31, 2010 11:42 AM Subject: RE: [Repeater-Builder] Duplexers Wow this must of Really been a Dumb question , No one answered it Will the Duplexer have any problems inside with Condensation from Heating up in use and Cooling down
Re: [Repeater-Builder] Moisture/condensation (was: Duplexers)
Wow...sounds like somehow, moisture was released inside the building. If it's 20ºF outside the building, and 22ºF inside the building, it's hard to imagine how frost could form on the equipment, since the relative humidity indors would have to be lower, unless...there was water forced up through a crack in the floor, etc. 73, Paul, AE4KR - Original Message - From: N1BUG To: Repeater-Builder@yahoogroups.com Sent: Tuesday, August 31, 2010 4:52 PM Subject: Re: [Repeater-Builder] Moisture/condensation (was: Duplexers) Condensation and moisture can be a strange thing... I have 2 meter and 440 repeaters in my own unheated building on a local hill. Several years ago in the middle of a cold Maine winter, both repeaters started having assorted audio problems and controller glitches. Upon arriving at the site I was horrified to find a thick layer of white frost completely covering every surface inside the building. Floor, walls, ceiling, every bit of equipment, cables, everything pure white and hairy with frost. I scraped away some frost and removed the cover from the repeater controller cabinet... and was even more horrified to find the controller PCB completely covered in frost! Couldn't even recognize the larger individual components on the board... What to do? I VERY slowly brought up the building temperature with a temporary heater over a period of a few days. The frost slowly vanished, not so much by melting and forming water but by dissipating into the air. Everything returned to functioning normally. The funny thing is, it never happened before or since. Just that one time. I never did figure out exactly what conditions caused it. Paul N1BUG
Re: [Repeater-Builder] DB212-3
Noise blankers also target broadband noise. If some computer is dumping right on your intended receive frequency, you're out of luck. 73, Paul, AE4KR - Original Message - From: Chuck Kelsey To: Repeater-Builder@yahoogroups.com Sent: Monday, August 30, 2010 3:10 PM Subject: Re: [Repeater-Builder] DB212-3 The radio I'm using in the mobile is a GE Orion with a noise blanker. However, a noise blanker is designed to help with impulse-type noise. Microprocessor hash and similar noise sources are continuous, so I doubt a blanker is very effective. The problem, in my mind, is the huge increase in this type of noise compared to 20 or 30 years ago. Chuck WB2EDV - Original Message - From: Oz-in-DFW To: Repeater-Builder@yahoogroups.com Sent: Monday, August 30, 2010 5:00 PM Subject: Re: [Repeater-Builder] DB212-3 On 8/30/2010 2:08 PM, Chuck Kelsey wrote: Doug, what were the State Police using for mobile radios back when you were involved? I'm finding that the newer, wider front end, radios don't hear as well as the old 0.5-1 MHz wide receivers did. I can hit my 6-meter repeater full quieting, yet sometimes can hardly hear it due to mobile environment noise that you can't avoid driving past (computers, LAN equipment, etc., etc.) Chuck WB2EDV I'll bet 99-44/100% of this is the lack of an effective noise blanker. I was running a LB SyntorX 9000 at the peak of the last cycle and it ran rings around everything else. It ran FULL band 10 and 6. Bench sensitivity of all the radios were pretty close, but the moto mobile noise blankers were a major ( 10 dB) advantage. I'll bet those 'old' radios have good noise blankers. -- mailto:o...@ozindfw.net Oz POB 93167 Southlake, TX 76092 (Near DFW Airport)
[Repeater-Builder] Running a Mastr II Repeater QRP
I'm working on a UHF ham repeater project for installation some time next year, and was getting set to build one based on 35-watt Mitreks. I've just been offered a 100-watt Mastr II UHF repeater, complete including the cabinet, just taken out of service in a switch to narrow-band equipment. I helped maintain a VHF Mastr II repeater for a club years ago, and once built a UHF repeater out of a converted mobile, so I know the beast a bit, but have two questions... I don't know the current frequency, but suspect it's in the 460/465 MHz range. Will it move down into the 440s without a lot of grief? Also, I don't need anywhere near 100 watts, and need to avoid abusing the good nature and power bill of my landlord. (Also hope to have battery backup.) Can the 100-watt UHF PA be jumpered from an intermediate stage to the filter, bypassing the final? I seem to recall these would run at something in the 10-25-watt range with such a mod. Or, is this just gross overkill for a local repeater, and the Mitrek-based idea more appropriate? Now, where's my hand truck... 73, Paul, AE4KR
Re: [Repeater-Builder] Running a Mastr II Repeater QRP
Understood. IIRC, the MII could use a homebrew supply which provides ~13.6 VDC, so long as the voltage always stays high enough to keep the linear regulator on the 10V card in its happy zone, right? - Original Message - From: Jeff DePolo To: Repeater-Builder@yahoogroups.com Sent: Monday, August 30, 2010 3:53 PM Subject: RE: [Repeater-Builder] Running a Mastr II Repeater QRP Also, I don't need anywhere near 100 watts... The driver is 40 watts, just bypass the final board. But if you're really trying to safe your landlord's electric bill, the ferro power supply is really what you should be eliminating...
Re: [Repeater-Builder] Running a Mastr II Repeater QRP
Kevin, I'll make a note and get back to you if we move forward, thanks! Is the base PA rated for continuous duty? - Paul, AE4KR - Original Message - From: Kevin King To: Repeater-Builder@yahoogroups.com Sent: Monday, August 30, 2010 4:49 PM Subject: RE: [Repeater-Builder] Running a Mastr II Repeater QRP I have a 40watt base PA ready to go if you would like to run that. -Kevin -- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Jeff DePolo Sent: Monday, August 30, 2010 5:53 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Running a Mastr II Repeater QRP
Re: [Repeater-Builder] Running a Mastr II Repeater QRP
Nate, I already know I'd love to have a MII, and the bulk won't be an issue getting it home or storing it, but the proposed site is on a rooftop. That part could get interesting. I may need to devise a truss...and something to hoist the repeater, too! (Rimshot.) This unit is very unlikely to be a modded station...it was originally spec'd for, and has been in, repeater service for years on a mountain top by the original owner. It is said to be spectacularly clean inside and out, and has never had an outage. (I know...two attributes which oddly seem to go together.) The ham repeater's purpose will be to support emergency prep nets and related ops in a couple of suburbs, and a high central point will be available, so a preamp may not be warranted. It may also get used in a crossband scheme during calmer times, and for other experiments in which the widest possible coverage would actually have some downside. Controller will very likely be my S-Com 7K. 73, Paul, AE4KR - Original Message - From: Nate Duehr To: Repeater-Builder@yahoogroups.com Sent: Monday, August 30, 2010 6:44 PM Subject: Re: [Repeater-Builder] Running a Mastr II Repeater QRP They're bulky, but you can't find anything on the market that will outperform them today for SELECTIVITY. You may want a pre-amp on the receiver for SENSITIVITY, depending on other factors of your antenna system and site selection and how far out you want it to hear. ...Other comments: When you get the station, post photos or look through the LBIs and see what (hopefully factory) configuration it's in. Some were repeaters, some were just stations... Anyway... you learn to love 'em and decide that the weight and bulk is worth it... :-) -- Nate Duehr, WY0X
Re: [Repeater-Builder] Duplexers
Chris, There aren't many ways around the laws of physics. If you can't get adequate physical separation, and can't afford a duplexer...perhaps you just can't afford to operate a repeater. Can you gather enough interested users, and get everyone to chip in for a duplexer? If not, maybe your local user community isn't large enough to need a 220 MHz repeater! You might be able to gather a group adequate to fund and support a 220 repeater if you got closer to the Charleston area, linked into a hub in Charleston, etc. Your elevation might have some definite linking possibilities if folks in Charleston wanted a 220 MHz hub that could get them coverage farther west on US 26, for example. Generally, if you need to raise money to get a project done, you need to be able to cover a population center large enough to include a bunch of potential users. Given your area's population growth, if you have the connections, getting the town or county to help fund a sanctioned emergency repeater system might be an avenue, but you'd better have enough users on 220 to make it work if it's ever called up. The economy will be against you in this pursuit; your population growth will be an advantage. Remember, finding the money to get it built and installed is only the start of the financial fun. You'll need an ongoing budget for maintenance and repair, or the machine will spend too much time down, and the users will wander off to other pursuits. Good luck! 73, Paul, AE4KR - Original Message - From: cmcclel...@aol.com To: Repeater-Builder@yahoogroups.com Sent: Monday, August 30, 2010 6:44 PM Subject: Re: [Repeater-Builder] Duplexers Thank you for your response. The problem is that the repeater is located on top of a building and the tower on that building is only about 20 feet tall. We can move the two antennas apart horizontally, but only 20 feet vertically. Duplexers are way too expensive and hard to find for the 200 Mhz band. We are running about 20 watts and the frequency separation is 1.6 mhz. Sometimes a week signal comes in and sometimes the transceiver is desensitizing the receiver and covers it up. Any suggestions? Thanks Chris In a message dated 8/30/2010 8:36:53 P.M. Eastern Daylight Time, wb6...@verizon.net writes: Chris, You do not have to use a duplexer, but it makes building a repeater SO much easier! Keep in mind that antenna separation usually means vertical separation, not horizontal separation. Moreover, the same isolation provided by 1000 feet of horizontal separation might be provided by 10 feet of vertical separation. The amount of isolation you need is based generally on the transmit power, frequency separation between TX and RX, and the sensitivity of the receiver. The receiver bandwidth and antenna types also play a factor. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Mackey Sent: Monday, August 30, 2010 4:44 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Duplexers Our club was recently given a 220 repeater. We have two seperate antennas. We do not have a duplexer. My question is do we have to have a duplexer? How can we keep the transmitter from desensitizing the receiver? The antennas are apart but can be moved farther. Thanks Chris Kg4bek
Re: [Repeater-Builder] Re: Fw: DON'T BUY IT AND DON'T USE IT !!!------READ IT
And yet, you're the one who hit reply and kept it going... 73, Paul, AE4KR - Original Message - From: Chris Robinson To: Repeater-Builder@yahoogroups.com Sent: Thursday, August 26, 2010 9:31 AM Subject: Re: [Repeater-Builder] Re: Fw: DON'T BUY IT AND DON'T USE IT !!!--READ IT ...This is not a religious sounding board, Please take your crap somewhere else... .
Re: [Repeater-Builder] Re: Motorola style Rack Clip Nuts
I once worked in the aftermarket autosound industry, where springy, one-sided blind nuts were used to mount speakers in places you couldn't see. They were supposed to catch on the lip of the speaker frame to keep from spinning, but it was easy to misalign them when you couldn't see what you were doing, so they'd spin, creating a significant hazard to fingers. They were also called Jesus nuts by my coworkers, probably named in a spontaneously outburst by some guy who was about to need a tetanus shot. 73, Paul, AE4KR - Original Message - From: Chuck Kelsey To: Repeater-Builder@yahoogroups.com Sent: Friday, August 20, 2010 2:47 PM Subject: Re: [Repeater-Builder] Re: Motorola style Rack Clip Nuts I agree with Skip. I always considered Tinnerman nuts as a one-sided unit, often used a few years back in the automotive industry. They also called them speed nuts. Chuck WB2EDV - Original Message - From: skipp025 skipp...@yahoo.com To: Repeater-Builder@yahoogroups.com Sent: Friday, August 20, 2010 4:35 PM Subject: [Repeater-Builder] Re: Motorola style Rack Clip Nuts Have a look (obviously the stainless one is on the right): http://www.arcomcontrollers.com/clips.jpg I've not heard this model U, C, Clip Nut ever called a Tinnerman, but McMaster-Carr sells it as a Clip-Nut. As a general rule I believe Tinnerman Nuts are normally one sided. I call it a U-Style Clip-Nut and they are obviously available in many flavors. http://www.mcmaster.com/#clip-on-nuts/=8hn41l It's McMaster-Carr so hold on to your wallet... but they do have everything. And they won't send out a Paper Catalog unless you have a previously verified connection with some higher authority. So use their fairly decent on-line catalog... They also deserve credit for super fast shipping. cheers, s. Yahoo! Groups Links -- No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.851 / Virus Database: 271.1.1/3083 - Release Date: 08/20/10 02:35:00
Re: [Repeater-Builder] Re: the non religious Jesus Nuts
Ahhh...gotta love Fridays! Yes...there is the Jesus nut on a helicopter, and a Jesus bolt in the rotorhead of a gyroplane, and fixed-wing pilots like to chide us about both. I like to ask them how things will go if the bolt holding the wing strut on a Cessna 172 lets go. Then, I remind them that during pre-flight inspection, I can see mine, and they can't see theirs! I'm still not sure how helicopters fly at night. How does the ground continue to repel them when it can no longer see how ugly they are? This is NOT an off-topic post. It's the first half of a metaphor. In aviation, we're taught to spend all our pre-flight time checking out the hardware, when 90% of the problems are pilot error. Go ahead, say it with me... In repeaters, we spend all our time up on the mountain in the dark risking snake bites and mouse-turd-borne diseases, when 90% of the issues are caused by the usersOK, 99%... ;^) 73, Paul, AE4KR - Original Message - From: cruising7...@aol.com To: Repeater-Builder@yahoogroups.com Sent: Friday, August 20, 2010 3:51 PM Subject: Re: [Repeater-Builder] Re: the non religious Jesus Nuts The ultimate act of courage in piloting a helicopter is accepting that the Jesus nut was probably supplied by the lowest bidder. In a message dated 8/20/2010 2:39:36 P.M. Pacific Daylight Time, skipp...@yahoo.com writes: Re: the non religious Jesus Nuts They were also called Jesus nuts by my coworkers, I thought a Jesus Nut was atop a helicopter holding things on or together. If it came off or failed, you normally had an expedited trip to Jesus if you believe in conventional religion. probably named in a spontaneously outburst by some guy who was about to need a tetanus shot. ... if you lost the Jesus Nut on your helicopter, I suspect you will quickly need more than a tetanus shot.
Re: [Repeater-Builder] Adding capacitors to lower electric bill
One company supplying power factor correction capacitors promotes their use on inductive loads only, where it might be a legitimate claim: http://www.greenenergycube.com/index.php?support-documentation 73, Paul, AE4KR - Original Message - From: Chuck Kelsey To: Repeater-Builder@yahoogroups.com Sent: Friday, August 20, 2010 7:00 PM Subject: [Repeater-Builder] Adding capacitors to lower electric bill A while back, maybe a year or two ago, there was a discussion on here where a list member had success adding a capacitor to his electric service which reduced his bill. It was debated for a while. ...
Re: [Repeater-Builder] MASTR II LOW BAND TUNING
...but it sure gives THEM a warm feeling! 73, Paul, AE4KR - Original Message - From: Jeff DePolo To: Repeater-Builder@yahoogroups.com Sent: Monday, July 05, 2010 8:08 PM Subject: RE: [Repeater-Builder] MASTR II LOW BAND TUNING I took a quick look at them, and what stands out like a sore thumb is 1.6 db insertion loss with a 150 watt power rating. That means they'll be dissipating close to 50 watts in such a small package. Doesn't give me a warm and fuzzy feeling... --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Eric Lemmon Sent: Monday, July 05, 2010 8:02 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] MASTR II LOW BAND TUNING I see what the sales flyer says, but the response plots show no real bandpass action. Indeed, the plots depict...
Re: [Repeater-Builder] OT:Printing google or Bing maps from the web
Don, There are no Shift, Alt or Ctrl keys needed for the capture. With the Map displayed on the screen, simply press [PrintScreen] unshifted. This puts the image on the Windows clipboard. Now... (1) Open MS Paint. (Start, All Programs, Accessories, Paint) (2) [Ctrl]+[V] pastes the image into Paint. (3) Select the area to be saved to eliminate uneeded stuff around the edges. (4) [Ctrl]+[X] snips out the selected area, which is now on the clipboard. (5) Move the cursor to the File menu at top of screen and select New. (Click no when asked if you want to save the current file.) (6) Staring from the new blank file displayed, [Ctrl}+[V} inserts the area selected from the original screen save into Paint. (7) Save it as a JPEG. (8) Use MS Windows Picture Fax Viewer to display and print, insert the image into a document, etc., lots of options. This seems like many steps, but it's actually pretty quick, and saving as a JPEG leaves many options. Works great during videos, too. 73, Paul, AE4KR - Original Message - From: Don Kupferschmidt To: Repeater-Builder@yahoogroups.com Sent: Tuesday, June 29, 2010 7:42 PM Subject: [Repeater-Builder] OT:Printing google or Bing maps from the web All, I'm trying to print a map which was brought up on either google or bing maps on the internet and then export it to a bmp or jpg file which then I can print to an ink jet printer. I've tried and tried to figure this out, but cannot to find a solution. Has anyone been successful in doing this? Or do I need more software? O/S is x/p Pro. TIA, Don, KD9PT
Re: [Repeater-Builder] Re: Harmful Taxing
Every ten minutes, it speaks in code. Hmm...maybe still works! ;^) - Original Message - From: and...@msu.edu To: Repeater-Builder@yahoogroups.com Sent: Monday, June 28, 2010 9:52 AM Subject: RE: [Repeater-Builder] Re: Harmful Taxing Quoting Yahoo ya...@icsradio.com: ...Well, since repeaterr mindlessly mimic what they hear, I'd say Rebublican... Switch to: Text-Only, Daily Digest . Unsubscribe . Terms of Use.
Re: [Repeater-Builder] OT: Motorola_Software_Users Yahoo group forum
I'm not seeing any of these messages, so they apparently aren't coming through the list. 73, Paul, AE4KR - Original Message - From: Don Kupferschmidt To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 30, 2010 11:45 AM Subject: [Repeater-Builder] OT: Motorola_Software_Users Yahoo group forum Hi to the group, Does anyone either 1) belong to this group or 2) know what is happening to this forum? I've been a subscriber to this list for a while now but it apparently got hacked by spam. As of late, there are emails being sent by the owner, manager and moderator stating that this group is going to be shut down and advises users to join another group listed in the email, but no information is given about the new group or how to join it. TIA, Don, KD9PT
Re: [Repeater-Builder] Re: mrs2000
Why, of course, it's what's found on the other side of the combiner from the MR2000. ;^) - Original Message - From: Mike Morris WA6ILQ To: Repeater-Builder@yahoogroups.com Sent: Sunday, May 16, 2010 2:32 PM Subject: Re: [Repeater-Builder] Re: mrs2000 What's an MRS2000 ? (from the subject line) As to the Code Plug Too New message go here:
[Repeater-Builder] PolyPhaser, or Stub?
Guys, I'm considering the relative value of various coax protection schemes for a planned UHF ham repeater. I know PolyPhaser is the industry standard, but I also know they don't last forever, and can cause problems with spurious emissions in some failure modes. A simple shorted quarter-wave stub on a tee will put the entire feedline at DC ground, but wouldn't be much of a match for even an indirect, nearby lightning strike. But...what if I could build a really stout quarter-wave stub out of non-ferrous metal, with enough diameter and wall thickness to put up a fight, or at least make the coax the fuse? Would I need to account for superheated air turning the cavity into a bomb when hit, or would the coax fail quickly enough? It would be fairly easy to construct out of copper, (and could be brazed rather than soldered,) but I'm likely to have to connect it to a large-gauge aluminum ground system on whatever rooftop I find for a site. Is there a good way to make this connection between dissimilar metals, or should I try to build it out of aluminum? Given the fact it will probably be connected in the feedline using a silver-plated tee anyway, am I overthinking the dissimilar metals issue? More important, is there something I'm missing in the comparison? A shorted cavity would seem to be a more elegant solution where DC does not need to be fed up the coax, and would have some mildly beneficial, if broad, bandpass characteristics. If you're a fan of the PolyPhaser aproach, which of their products would be preferred on a 440 MHz ham repeater? This system is being designed for limited HAAT and coverage, and we expect to be at a site in an industrial area with no other RF systems in close proximity. 73, Paul, AE4KR
Re: [Repeater-Builder] PolyPhaser, or Stub?
Nate, I appreciate the thoughts. I've been blessed to be around some really nice broadcast sites, and one of the telco microwave sites, during my career, and I'm not sure which is worse...having a site attacked by the new engineers who only know card-swapping, having it attacked by bean counters, or having it attacked by meth addicts looking to resell to copper. I worked at a 10 kW broadcast station that had the ground radials ripped up one night by the druggies, while the site was hot. That's ambition! The site I anticipate will have no tower, no building, therefore no indoors, no halo, and improvisation will be required. Fortunately, also no AC line, likely solar on this one. I expect the challenge will be like the last site I had in Florida, where we had a building rooftop all to ourselves, but had to adapt to the extensive groundiing system built for the lightning rods using big, stranded, aluminum cables. I would disagree that anything used to short the stub would explode...I'm envisioning a cavity CNC'd out of aluminum billet. Certainly more meat than the path through a PolyPhaser. But - insurance underwriters love PolyPhasers, and there's always a reason. Regarding AC line being the biggest PITA lightning-wise, phone lines have to be ranked up there pretty high, too... 73, Paul, AE4KR - Original Message - From: Nate Duehr To: Repeater-Builder@yahoogroups.com Sent: Wednesday, May 12, 2010 1:13 AM Subject: Re: [Repeater-Builder] PolyPhaser, or Stub? I can only speak from experience here... - Tower grounds done correctly - Building entrance panel made of copper - EVERYTHING entering the building goes through the panel and through a Polyphaser - Overhead halo ground for all equipment indoors, and/or if you must, copper strap on a concrete floor - Cabinets grounded to the halo or floor system...
Re: [Repeater-Builder] @#@*$%*((!!
Oh, the irony...If bandwidth is an issue for you, suggest not sending the same post twice! - 73, Paul, AE4KR - Original Message - From: dennuszabawa To: Repeater-Builder@yahoogroups.com Sent: Tuesday, May 04, 2010 5:34 AM Subject: [Repeater-Builder] @#@*$%*((!! OK, now that I have your attention. The two things that have driven me from Yahoo Groups are: Hijacking Threads: IF you can't figure out how to start a thread on a new topic, please, BACK AWAY FROM THE KEYBOARD! Not Trimming Replies: What is the sense of a 110KB+ reply that is 90% repeated material. Again, IF you can't figure out how to trim your reply, please, BACK AWAY FROM THE KEYBOARD! Consider this to be an intervention.
Re: [Repeater-Builder] Direct Strike Lightning Detector
Well sure...if you take the shortcut! ;^) I gotta remember not to post after 1am... - Original Message - From: John J. Riddell To: Repeater-Builder@yahoogroups.com Sent: Tuesday, April 27, 2010 3:52 AM Subject: Re: [Repeater-Builder] Direct Strike Lightning Detector But Paul...Toronto is not near Lake Erie ! It's on Lake Ontario:-)) John VE3AMZ Waterloo, Ontario
[Repeater-Builder] Mitreks as UHF Repeaters?
After a few years on the sidelines, it looks as if I'm going to be jumping back into repeater ownership. I have a few nice pieces left from my last adventure, including a TX/RX duplexer and a loaded S-COM 7K, but I'm pondering choices in RF decks. This will be a local UHF machine designated as an asset for a emergency net in a suburban area, at a modest height, and the only RF device at its site. I have two Mitrek 30w UHF mobile radios, and am aware of their duty-cycle limitations, but would like to consider using them. They have channel elements, and I'm not averse to spending the money to have the elements redone properly. Looks like the pair will be 447.xx transmit / 442.xx receive. I have a couple specific questions about these radios... (1) If Mitreks are converted for full duplex, how well do they work? I'd like to have a complete, swappable RF setup, so trips to the site are short, and repairs can be done on my bench at home. (As opposed to requiring the two radios as separate receiver and transmitter.) (2) Would it be a reasonable pursuit to adapt a larger heatsink, and would that safely allow 100% duty cycle at 25-30 watts? (I'm philosophically opposed to fans which introduce the opportunity for a bearing to take the machine out of service.) (3) Any comments on the front ends? (4) I know these lack the sophistication of the Micor mobiles. Is the lack of a circulator a big deal in this application, at an isolated site with no other transmitters? (5) Was Motorola's quality in the Mitrek era still good enough to make a Mitrek preferred over, say, synthesized commercial transmitter boards from lesser manufacturers, but of more current vintage? All comments welcome. 73, Paul, AE4KR
Re: [Repeater-Builder] Mitreks as UHF Repeaters?
Tim, My plan at this point is to convert them to full duplex, so I can use the second Mitrek to prepare a complete, plug-in, standby set of RF decks. The mods look very straightforward, but I was wondering if there were any gremlins people discovered. Your heatsink approach, however, is exactly what I was talking about. I have several very large heatsinks originally designed for use with big SCR switching circuits which look to be more than generous for a 30w PA at 100% duty cycle. My first repeater was built from a 2w Repco exciter board repurposed from RFID service. It was supposedly rated for continuous duty, but had to run very hot to dump the heat it produced through the little aluminum tab mounted to its own PC board within the case. I fashioned a new tab with a 90º twist which allows sinking the little PA to the case itself, and it never got above warm to the touch, even after hours key-down. Guys, I appreciate all the input. 73, Paul, AE4KR - Original Message - From: w7...@comcast.net To: Repeater-Builder@yahoogroups.com Sent: Monday, April 26, 2010 10:16 AM Subject: Re: [Repeater-Builder] Mitreks as UHF Repeaters? Isn't the rpt. going to be built using (2) Mitrex, thus shielding should not be a problem. I have, in the past (with the help of a Bridgeport mill), fashioned Larger Heatsinks, that bolt onto the orig. Mitrex heat sinkseems to dissipate heat well...
Re: [Repeater-Builder] Mitreks as UHF Repeaters?
Ken, Correct, of course, but I'm assuming that in a 30w PA, smaller components not somehow directly sunk to the main chassis heatsink will reach their max operating temps in a very few seconds of key-down, and therefore have to be spec'd the same for intermittent duty PAs as if they would if they were in continuous duty. I'm willing to roll those dice, especially if a similar design was used by the manufacturer in repeater service. There seem to be plenty of Mitreks used as repeaters in the past, so I think we'll be OK. I'm gathering, however, that as cheap as these radios have become, it mike just make sense to use two radios, and source more spares. 73, Paul, AE4KR - Original Message - From: Ken Arck To: Repeater-Builder@yahoogroups.com Sent: Monday, April 26, 2010 12:01 PM Subject: Re: [Repeater-Builder] Mitreks as UHF Repeaters? At 10:49 AM 4/26/2010, Paul Plack wrote: Your heatsink approach, however, is exactly what I was talking about. I have several very large heatsinks originally designed for use with big SCR switching circuits which look to be more than generous for a 30w PA at 100% duty cycle. Remember folks that heatsink capability is not the only issue when it comes to duty cycle. Components such as caps, resistors, diodes and even pc board traces all factor in as well and, even though you might be able to suck the heat away from the transistors adequately, other parts aren't necessarily up to the task and could very well fail. Ken -- President and CTO - Arcom Communications Makers of repeater controllers and accessories. http://www.arcomcontrollers.com/ Authorized Dealers for Kenwood and Telewave and we offer complete repeater packages! AH6LE/R - IRLP Node 3000 http://www.irlp.net We don't just make 'em. We use 'em!
Re: [Repeater-Builder] Mitreks as UHF Repeaters?
Kris, looking at the pictures of the Mitreks of various power levels, I'm not confident there would be holes and heatsink pads in the high-power case that line up with the board mounts and needed contact points of the low-power PA board. But yes - I had considered that approach. I am completely unfamiliar with the Syntor, cost, availability, etc., but I'm also early in the process of nosing around locally. I'm willing to look at any plentiful, high-quality radios for the conversion. 73, Paul, AE4KR - Original Message - From: Kris Kirby To: Repeater-Builder@yahoogroups.com Sent: Monday, April 26, 2010 12:26 PM Subject: Re: [Repeater-Builder] Mitreks as UHF Repeaters? On Mon, 26 Apr 2010, Paul Plack wrote: Remember, the 100W Mitrek had a heatsink that was rated for 35W and used the duty cycle to keep things cool. If you do a case swap from a 30W radio into a 100W case, you could be fine for 100%, barring excessive temperature climb. My druthers would be to use an Original Syntor. It's got the helicals of a Mitrek, and the programming of a PROM. At $10 per frequency change (the going rate of the PROM chip), it's still cheaper than the Mitrek and uses the Mitrek/Motrac accessories. -- Kris Kirby, KE4AHR Disinformation Analyst
Re: [Repeater-Builder] Mitreks as UHF Repeaters?
Jeff, I appreciate the thoughts. Anytime I've looked at a scheme which allows simply swapping the TX and RX to get back on the air, I arrive at the same conclusions... (1) If I took a lightning hit at the site, I'd want my spares to have been stored somewhere else. (2) Once I swap the TX and RX, I still can't bring either home for repair without taking the machine off the air. As far as the automated switchover, the 7K has three receiver and two transmitter ports, so I wouldn't even need coax relays to provide remote swap capabilities. I could just crystal each radio for simplex, wire both receivers and both transmitters into the controller, issue a remote DTMF command to swap them, and instantly implement a second repeater on the upside-down split. I think my answer is going to end up being building a stash of spares, and using two radios. 73, Paul, AE4KR - Original Message - From: Jeff DePolo To: Repeater-Builder@yahoogroups.com Sent: Monday, April 26, 2010 12:11 PM Subject: RE: [Repeater-Builder] Mitreks as UHF Repeaters? Because of the internal desense issue, I'd build them the same, but operate the two radios separately. That is, use one as a transmitter and the other as the receiver by default. No duplex mods required. If the Tx dies on one, swap the system cables around to make the formerly-transmitter radio the receiver, and vice-versa. You could even automate the changeover via a couple of coaxial relays and some simple homebrew transistor and/or relay logic tied into your controller. --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Paul Plack Sent: Monday, April 26, 2010 1:49 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Mitreks as UHF Repeaters? ? Tim, My plan at this point is to convert them to full duplex, so I can use the second Mitrek to prepare a complete, plug-in, standby set of RF decks. The mods look very straightforward, but I was wondering if there were any gremlins people discovered. Your heatsink approach, however, is exactly what I was talking about. I have several very large heatsinks originally designed for use with big SCR switching circuits which look to be more than generous for a 30w PA at 100% duty cycle. My first repeater was built from a 2w Repco exciter board repurposed from RFID service. It was supposedly rated for continuous duty, but had to run very hot to dump the heat it produced through the little aluminum tab mounted to its own PC board within the case. I fashioned a new tab with a 90º twist which allows sinking the little PA to the case itself, and it never got above warm to the touch, even after hours key-down. Guys, I appreciate all the input. 73, Paul, AE4KR - Original Message - From: w7...@comcast.net mailto:w7...@comcast.net To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder@yahoogroups.com Sent: Monday, April 26, 2010 10:16 AM Subject: Re: [Repeater-Builder] Mitreks as UHF Repeaters? Isn't the rpt. going to be built using (2) Mitrex, thus shielding should not be a problem. I have, in the past (with the help of a Bridgeport mill), fashioned Larger Heatsinks, that bolt onto the orig. Mitrex heat sinkseems to dissipate heat well... No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.801 / Virus Database: 271.1.1/2792 - Release Date: 04/26/10 02:31:00
Re: [Repeater-Builder] Mitreks as UHF Repeaters?
Ken, Thanks, appreciate the link. This document adds a few details to what I had on hand. Good to know the high-split Mitreks weren't prone to the spurs when duplexed. Also encouraging to read that the 30w radios will run 100% at 20w with the smaller heatsink. That's probably all the power I'd need in my application. 73, Paul, AE4KR - Original Message - From: Ken Arck To: Repeater-Builder@yahoogroups.com Sent: Monday, April 26, 2010 1:09 PM Subject: Re: [Repeater-Builder] Mitreks as UHF Repeaters? At 11:47 AM 4/26/2010, Paul Plack wrote: Ken, Correct, of course, but I'm assuming that in a 30w PA, smaller components not somehow directly sunk to the main chassis heatsink will reach their max operating temps in a very few seconds of key-down, and therefore have to be spec'd the same for intermittent duty PAs as if they would if they were in continuous duty. ---There are several components that are common failures in Mitreks used in duty cycle apps greater than it was designed for. One should read the following: www.ecso.com/srca/modmitrek _files/mitrex_mod.pdf Just sayin' -- President and CTO - Arcom Communications Makers of repeater controllers and accessories. http://www.arcomcontrollers.com/ Authorized Dealers for Kenwood and Telewave and we offer complete repeater packages! AH6LE/R - IRLP Node 3000 http://www.irlp.net We don't just make 'em. We use 'em!
Re: [Repeater-Builder] 3' motorola or GE cabinet wanted.
Larry, are any of your cabinets outdoor types? I'm in Salt Lake City, but have relatives near you who could pick up store, and might be interested. - Paul, AE4KR - Original Message - From: larryjspamme...@teleport.com To: Repeater-Builder@yahoogroups.com Sent: Monday, April 26, 2010 1:43 PM Subject: Re: [Repeater-Builder] 3' motorola or GE cabinet wanted. Too bad you're so far away (I'm in Portland, OR). I'm just getting ready to list some on the local craigslist - my garage is overflowing and some cars need the space. I have some of the deep Quantar/MICOR type cabinets - the short ones, medium height, and 5-foot tall ones. And one - 40 tall GE MASTR II Cabinet. All of the Motorola cabinets are the deep ones that would hold repeaters with duplexers, etc. IF they don't sell locally, they're off to the metal scrapper. Larry
Re: [Repeater-Builder] Mitreks as UHF Repeaters?
Tom, Yes - the spurs mentioned were not the ones created by running the power too low. Apparently, the 406-420 Mitreks had a separate issue which was not dependent on power setting, in which the local oscillator for the receiver would get into the exciter's multiplier chain. I think almost any of these discreet-component PAs wander off the spec chart if you run them too far below rated power. My last UHF repeater was a 35w Mastr II, and it started getting pretty gritty below about 18 watts. 73, Paul, AE4KR - Original Message - From: TGundo 2003 To: Repeater-Builder@yahoogroups.com Sent: Monday, April 26, 2010 3:26 PM Subject: Re: [Repeater-Builder] Mitreks as UHF Repeaters? I ran a Duplexed 50W UHF mitrek @30W with a Fan on the heat sink for 5 years without a problem. I Upgraded that site to a full blown UHF Micor Repeater that is 75W. As expected on the TX the range is better, but the Micor is also a slight bit better on the RX as well. I will probably re-use the mitrek radio in a future RX site since I have it and the channel element. That being said, the Mitrek served me well and was a great way to get the repeater going. If I did Mitreks again I would use two radios, not because I had any problems, but because of the redundancy it would offer. TX or RX dies, just swap radios and your back on the air. As a side note to running a single duplexed radio, I never had any measurable de-sense, but I did get spurrs and crap when I tried setting the TX power too low. Its happiest at 50-75% of its rated power. Tom W9SRV --- On Mon, 4/26/10, Paul Plack pl...@xmission.com wrote: From: Paul Plack pl...@xmission.com Subject: Re: [Repeater-Builder] Mitreks as UHF Repeaters? To: Repeater-Builder@yahoogroups.com Date: Monday, April 26, 2010, 3:07 PM Ken, Thanks, appreciate the link. This document adds a few details to what I had on hand. Good to know the high-split Mitreks weren't prone to the spurs when duplexed. Also encouraging to read that the 30w radios will run 100% at 20w with the smaller heatsink. That's probably all the power I'd need in my application. 73, Paul, AE4KR - Original Message - From: Ken Arck To: Repeater-Builder@yahoogroups.com Sent: Monday, April 26, 2010 1:09 PM Subject: Re: [Repeater-Builder] Mitreks as UHF Repeaters? At 11:47 AM 4/26/2010, Paul Plack wrote: Ken, Correct, of course, but I'm assuming that in a 30w PA, smaller components not somehow directly sunk to the main chassis heatsink will reach their max operating temps in a very few seconds of key-down, and therefore have to be spec'd the same for intermittent duty PAs as if they would if they were in continuous duty. ---There are several components that are common failures in Mitreks used in duty cycle apps greater than it was designed for. One should read the following: www.ecso.com/ srca/modmitrek _files/mitrex_ mod.pdf Just sayin' - - - - - - - --- President and CTO - Arcom Communications Makers of repeater controllers and accessories. http://www.arcomcon trollers. com/ Authorized Dealers for Kenwood and Telewave and we offer complete repeater packages! AH6LE/R - IRLP Node 3000 http://www.irlp. net We don't just make 'em. We use 'em!
Re: [Repeater-Builder] Direct Strike Lightning Detector
Jesse, A radio engineer in Atlanta years ago told me a neat trick he said allows confirming a strike, and estimating the current it produced. It involves rexcording an audio tone on a piece of magnetic tape several feet long, sealing it in a weatherproof, non-conductive tube, and positioning it perpendicular to a tower leg. If lightning strikes, the magnetic flux produced around the conductor will vary proportionate to the current, and playing back the tape will reveal an erased portion which can be measured for its physical length. I have no idea how well that would actually work, or how to calculate the current based on how many inches of tape are erased. These days the only magnetic tape machines left in common use are old cassette decks, but it might be worth a piece of PVC pipe and some glue to try it. If you just want to know if it's hit, set up a vertical conductor some distance from the tower, but well within its cone of protection, connected through a fuse to an independent ground. If the tower gets smacked, you can bet some serious current will be induced in a 10-foot vertical wire. Years ago, an engineer for WBEN radio in Buffalo told me that on summer days when thunderstorms would hit the Toronto area across Lake Erie to the north, a hit on a radio tower up there would produce a spark across the ball gaps on the towers in Buffalo. That's 90 miles! 73, Paul, AE4KR - Original Message - From: Jesse Lloyd To: Repeater-Builder@yahoogroups.com Sent: Monday, April 26, 2010 11:32 PM Subject: [Repeater-Builder] Direct Strike Lightning Detector Hey All, I am trying to think of a way to detect if a tower at one of our sites gets a direct hit. I was thinking of paralleling a ground strap with a 10mA amp glass fuse. Maybe make the two connections to the ground stap 2 ft apart and use a fuse holder for fuse testing and replacement. I suspect the fuse would blow if any significant current went down the ground strap (or would the whole thing melt? I suppose either way I'd know!). Ideas? I live in an area that doesn't see a lot of lightning, I'm curious if the tower gets hit. Jesse
Re: [Repeater-Builder] OT:Antenna height restrictions and PRB-1
Don, The ARRL would be a good place to start on this, but it probably will have nothing to do with the FCC. PRB-1 requires reasonable accommodation by locals. It doesn't give hams carte blanche. If the family didn't dot the i's and cross the T's with the locals, which in many cases requires filing engineering data to support choices in foundation design and guying schemes, etc., PRB-1 won't help. 73, Paul, AE4KR - Original Message - From: Don Kupferschmidt To: Repeater-Builder@yahoogroups.com Sent: Wednesday, April 21, 2010 2:24 PM Subject: [Repeater-Builder] OT:Antenna height restrictions and PRB-1 Hi group, First off, hopefully this post is not going to conflict with Kevin's restrictions on the FCC rules regs on this forum. I'm looking for some information from others, that in the past, have had situations with local / county / state governments concerning antenna height and what their outcomes were. There's a situation right now in southeastern Wisconsin where a 10 year old ham is having issues with neighbors and the local government about his tower height. You can read the full story here: http://www.todaystmj4.com/news/local/91663619.html Specifically I'm looking for any situation that happened in the past with you and your government that you had and how it was resolved, both bad and good. Kevin, if this conflicts with your rules then please direct the membership to my private email, dkupfers at sbcglobal dot net. TIA in advance to all that respond. Don, KD9PT
Re: [Repeater-Builder] Re: OT:Antenna height restrictions and PRB-1
Chuck, I actually got just the opposite intent. The mention of his handicap and community contribution through amateur radio paint a clear, sympathetic position. The reporter's job is to present both sides of the story. Accurately reporting the position of an opposing neighbor is required for fairness, and while the neighbor is obviously not well-versed in engineering principles, there were no facts skewed by the reporter. For anyone in the town not living in this thing's shadow, this story will tug the heartstrings in the boy's direction, not against him. I have a background in news, and also some experience being misquoted. This reporter did a way-above-average job of getting it right, especially for local media in a small market. Most coverage of ham issues villifies us from the start. We should all hope for something this fair. 73, Paul, AE4KR - Original Message - From: Charles Mills To: Repeater-Builder@yahoogroups.com Sent: Wednesday, April 21, 2010 5:28 PM Subject: Re: [Repeater-Builder] Re: OT:Antenna height restrictions and PRB-1 The article was written very poorly and the facts skewed to bully a handicapped child. “They started off with just a little antenna which was fine then the monstrosity came about the big tower and that's the one we were really worried about. We do see it rocking back and forth,” Eric Scott said. Of course it rocks back and forth...that's what the guy with the PE stamp designed it to do. I somehow don't see a Pulitzer in that journalist's future. Sorry again Kevin for the bandwidth here. Chuck On Wed, Apr 21, 2010 at 7:20 PM, wb6dgn tallins...@yahoo.com wrote:
Re: [Repeater-Builder] Re: D-Star (Protocol and Repeaters)
Old-fashioned? If you take being fashionable out of the argument, analog NBFM has some advantages which may not be appreciated until they're gone, particularly in emergency ops. Interoperability has been covered already, but there are some more subtle advantages to analog. If you have a station getting into the system only intermittently, is the operator being called away from the mic by local circumstances, or is he not making the repeater? Is it fading on the path, or a dying battery? Or, is something interfering with him on the input? How will you know? If it was analog, you could troubleshoot instantly, in your head, just by listening to the output. One of the problems facing LMR is the retirement of the last generation of techs who've ever heard picket-fencing. There is an intuitive understanding of issues such as multipath we all acquired using NBFM. Some of the new kids who've only played with digital have read about multipath, and maybe learned how to predict or measure it, but they'll have to look in a book to know how to fix it. Will they even think to try moving the car 3 inches to see if it works now? In emergencies, you may also miss out on information contributed by someone overhearing your conversation in some digital scenarios. There's also listenability. Given the choice between an analog NBFM system set up properly, and a D* repeater, I know which I'd rather have playing in my headphones for 8 hours at a Red Cross shelter. (Disclaimer: I also still prefer a good AM signal to SSB, and good vinyl audio recordings to 32K MP3s. ;^) 73, Paul, AE4KR - Original Message - From: John Szwarc To: Repeater-Builder@yahoogroups.com Sent: Monday, April 05, 2010 5:10 AM Subject: RE: [Repeater-Builder] Re: D-Star (Protocol and Repeaters) ...Maybe there is something they could learn from D-STAR? Maybe they could find ways to to improve it? Of course that won't happen if they are too busy trying to talk people out of it in favor of P25 or old fashioned analog... --
Re: [Repeater-Builder] Fwd: access gate accident
Yikes! Pardon me while I go get a tetanus shot! 73, Paul, AE4KR - Original Message - From: Mike Morris WA6ILQ To: Repeater-Builder@yahoogroups.com Sent: Wednesday, March 31, 2010 12:57 AM Subject: [Repeater-Builder] Fwd: access gate accident Look at all four pictures to see how lucky this guy really was. I'll bet that the first thing the gentleman driver checked was to see if Mr. Wiggles and his two neighbors were still there.
Re: [Repeater-Builder] 449 MHz Wind Profiler Radar?
Nate, as noted in the original posting, (below,) they've been at 404 MHz since 1992, and they're apparently wide enough to be taking out 406 MHz personal locator beacons. Granted, that would be a bigger issue for satellites looking down at radar pointing up, but it'll probably still be Son of Pave Paws. 73, Paul, AE4KR - Original Message - From: Paul Plack To: Repeater-Builder@yahoogroups.com Sent: Tuesday, March 30, 2010 8:27 PM Subject: [Repeater-Builder] 449 MHz Wind Profiler Radar? Did I miss this in an earlier thread, or is this a surprise? Paul, AE4KR Honeywell Wins Contract to Build 449 MHz Wind Profiler PHOENIX, March 29, 2010 -- Honeywell (NYSE: HON) today announced that it has been awarded a $49 million contract to upgrade the National Weather Service's radar wind profiler network that will predict severe storms earlier and provide the public with more accurate warnings of upcoming storms. For nearly two decades, ground weather radar improvements have been mostly incremental - yet weather patterns and storms around the globe have become more severe, said Vince Trim, president, Honeywell Technology Solutions, Inc. Honeywell is building a ground radar wind profiler network that can predict severe storms earlier and more reliably while better able to withstand hurricane force winds year after year. Honeywell's work on the production phase of the Next Generation National Oceanic and Atmospheric Administration (NOAA) Profiler Network contract includes upgrading the NOAA network of wind profilers that provide upper air wind data for crucial weather forecasting tasks. The NOAA Profiler Network has been operating continuously since 1992 and the equipment is now unsupportable. Honeywell's solution, which includes upgrades to the antenna, RF hardware, signal processing, networking, and other system components will provide the technology improvements to bring the profiler network up to a supportable, maintainable, and reliable level. Honeywell will change the radio frequency of existing 404 MHz profilers by replacing them with 449 MHz systems. This will prevent the existing interference with search and rescue satellite-aided tracking transponders...
Re: [Repeater-Builder] Re: if you have a commercial licenses check it on the fcc site
I got the First Phone about the same time, and about the same age. I was a budding DJ, and there were AM stations with complex directional arrays which would only hire night DJs with the First, because they'd be working alone in the building and were required to have a First at the control point. I still have that original certificate, with CANCELLED stamped across it, in a little picture frame. You could ask to get them stamped and returned to you when they expired, I suppose for just that purpose. Someday I'll be asked, Grandpa, what's that on your wall? What's radio? ;^) Paul, AE4KR - Original Message - From: Ralph Mowery To: Repeater-Builder@yahoogroups.com Sent: Tuesday, March 30, 2010 8:50 AM Subject: Re: [Repeater-Builder] Re: if you have a commercial licenses check it on the fcc site It was not worth much around 1971 or 72 when I passed the first class. I was about 21 at the time. I had never seen a TV transmitter and only got to look into a 1000 watt AM station control room and could see the tubes through a glass window. Passed it the first time. I only wanted the second class, but it only cost $ 1.00 more to take the first class
[Repeater-Builder] 449 MHz Wind Profiler Radar?
Did I miss this in an earlier thread, or is this a surprise? Paul, AE4KR Honeywell Wins Contract to Build 449 MHz Wind Profiler PHOENIX, March 29, 2010 -- Honeywell (NYSE: HON) today announced that it has been awarded a $49 million contract to upgrade the National Weather Service's radar wind profiler network that will predict severe storms earlier and provide the public with more accurate warnings of upcoming storms. For nearly two decades, ground weather radar improvements have been mostly incremental - yet weather patterns and storms around the globe have become more severe, said Vince Trim, president, Honeywell Technology Solutions, Inc. Honeywell is building a ground radar wind profiler network that can predict severe storms earlier and more reliably while better able to withstand hurricane force winds year after year. Honeywell's work on the production phase of the Next Generation National Oceanic and Atmospheric Administration (NOAA) Profiler Network contract includes upgrading the NOAA network of wind profilers that provide upper air wind data for crucial weather forecasting tasks. The NOAA Profiler Network has been operating continuously since 1992 and the equipment is now unsupportable. Honeywell's solution, which includes upgrades to the antenna, RF hardware, signal processing, networking, and other system components will provide the technology improvements to bring the profiler network up to a supportable, maintainable, and reliable level. Honeywell will change the radio frequency of existing 404 MHz profilers by replacing them with 449 MHz systems. This will prevent the existing interference with search and rescue satellite-aided tracking transponders...
Re: [Repeater-Builder] 10 Meter Questions
Mike, As others have noted, receiver selectivity and transmitter cleanliness will determine how far apart the sites need to be. All transmitters in the system must be ID'd. Various schemes are possible, and the FCC is not going to get so specific here so as to stifle technical innovation. (Although it wouldn't be the first time.) The bottom line is compliance with the rules. 97.3(6) defines automatic control as: The use of devices and procedures for control of a station when it is transmitting so that compliance with the FCC Rules is achieved without the control operator being present at a control point. If you create a kluge of a control scheme which proves unreliable in ID-ing as required, you'll run afoul of 97.101(a), which states: In all respects not specifically covered by FCC Rules each amateur station must be operated in accordance with good engineering and good amateur practice. If you ID the whole system by asking users to do it on the input, you're using a procedure to control the sending of the system ID, which satisfies 97.3. But on a band where propagation guarantees users not familiar with your procedure, random noise, or users of other, distant repeaters getting into yours by mistake, you'll end up violating the ID requirement often. I would expect to be cited for violating 97.101 in this case. If you use a traditional, Morse-audio ID on the outgoing link from the receive site, it will also ID the transmit side. But you're still vulnerable to having unidentified transmissions on the repeater output if something other than the link gets into your link receiver, (such as intermod or intentional, unauthorized users.) From a practical standpoint, there's not much excuse these days for using only one controller. It's ridiculously cheap now to put a separate, very basic controller at the one site, and a more elaborate controller with any desired bells whistles at the other site. Run the main controller with zero hang-time on the link, so you can use a timeout timer on the controller at the transmit site. The only downside to two controllers is double IDs, and there are ways to minimize that. (Have a link ID detector at the transmit site to reset the ID timer there; notch the audio frequency of the link ID at the transmit site; etc.) Or, just pick different audio frequencies so you can tell them apart, and let all the IDs be heard. Hams used to be proud of Morse code. ;^) 73, Paul, AE4KR - Original Message - From: N8FWD To: Repeater-Builder@yahoogroups.com Sent: Monday, March 29, 2010 6:42 AM Subject: [Repeater-Builder] 10 Meter Questions How far apart does my TX and RX in air miles on 10 meters have to be for a 150 watt transmitter? Can I put a ider on the rx site and let it id through the link and through the transmitter and be legal or do I have to Id at both sites? Thanks Mike N8FWD
Re: [Repeater-Builder] Test
They're being intercepted and screened by ebay before posting. - Original Message - From: kc8gpd To: Repeater-Builder@yahoogroups.com Sent: Wednesday, March 17, 2010 1:06 PM Subject: [Repeater-Builder] Test seems to be a long delay between posting messages and them showing up.
Re: [Repeater-Builder] cor location in an ic-2200h
Russ, you may have to spend more on whatever you're using for power than you're saving with those radios, as they pull 1.6 amps combined even on standby receive. Also, develop a plan to keep the transmit radio's heatsink cooled, even in low power mode. But plunging ahead... Your controller can work with either COS (carrier-operated switch) or derive that signal itself. If you can find COS in the Icom radio, you don't need discriminator audio, and can couple audio from anyplace handy, including the external speaker jack if it won't be accessible to passersby. You will need to lift one side of a capacitor on the controller board to use de-emphasized, non-discriminator audio. On the other hand, if you can provide the controller discriminator audio, you don't need COS - the controller will make its own. The CES docs actually seem to favor this approach. The 2200 doesn't provide the needed signals on its accessory connector, but there are leftover pins there you could use to get disciminator audio and COS out of the radio cleanly. Get the owners and service manuals, available through online search. 73, Paul, AE4KR - Original Message - From: Russell To: Repeater-Builder@yahoogroups.com Sent: Monday, March 15, 2010 11:33 PM Subject: [Repeater-Builder] cor location in an ic-2200h Hi, I am building a portable repeater for our ARES Club. I have 2 Icom IC-2200H 2 mtr units, a ces rm-10 controller. I am new at this building, and cannot decipher the info given by the controller instructions. It advises to use the radio cor connection and here is where I'm stumped. It also wants a connection at the output of the discriminater circuit. I have been a tech over 35 years, this issue is causing my teeth to fall out, I already lost most of my hair. I would really appreciate any help you might have. 73==Dan w2rdt BTW: I know these are not the best units to work with. Financially right now, it is all we could afford.
Re: [Repeater-Builder] cor location in an ic-2200h
Russ, what is your plan for duplexing? Those radios won't play well a few feet and 600 kHz apart. - 73, Paul AE4KR - Original Message - From: Russell Trippy To: Repeater-Builder@yahoogroups.com Sent: Tuesday, March 16, 2010 2:18 AM Subject: Re: [Repeater-Builder] cor location in an ic-2200h Thanks Nate, we are using radios at hand. we are a new club and are ARES in this county. I am building this unit just for call outs. We are using 2 mtr mainly due to not much activity on 70 ctmrs. I have built some cu copper 2mtr loops, I cannot believe the performance these little loops give out. Everything about this portable repeater is an adventure, I have hand made just about everything in this system. The cabinet has locks to keep wondering minds, dual fans, and a set of 100 amp gel cell batteries thrown in for power. Will always be with my truck, so I have power there as well. Your input is greatly appreciated.
Re: [Repeater-Builder] Re: Sorta OT: Looking for a couple of items
How do these transmitters play at crowded sites? I've heard some accounts of broadband noise problems for other tenants when high-power Glenayre equipment went in... 73, Paul, AE4KR - Original Message - From: Joe To: Repeater-Builder@yahoogroups.com Sent: Sunday, March 14, 2010 8:59 PM Subject: Re: [Repeater-Builder] Re: Sorta OT: Looking for a couple of items I maintained a 900MHz Glenarye digital simulcast system here in Connecticut years ago and played with the analog mode, it worked nice...
Re: [Repeater-Builder] Dual receivers on one antenna for RX only site
OK, question... If you put a cable which is 1/4-wavelength at VHF between the T and the UHF cavity, it's 3/4-wavelength at UHF. Since any odd multiple of a quarter wavelength will invert the impedance, what will this really accomplish on the UHF cavity side? The dual-band diplexers are usually high-pass/low-pass arrangements, and lose something like 0.2 dB while providing 40 dB or more isolation. Assuming you get a real one, and not something made with PIM-prne materials, would this not be a safer bet? Or, am I missing something? (It's happened before...) 73, Paul, AE4KR - Original Message - From: Gary Schafer To: Repeater-Builder@yahoogroups.com Sent: Tuesday, March 09, 2010 4:53 PM Subject: RE: [Repeater-Builder] Dual receivers on one antenna for RX only site The UHF cavity loop provides a short circuit at the VHF frequency but the quarter wave cable from it transforms the short to an open (high impedance) at the T connection so you get no attenuation of the VHF signal there. The VHF signal then passes to the VHF cavity as if the UHF cavity was not there. The same thing happens to the UHF signal going to the other cavity...
Re: [Repeater-Builder] Re: Someone still loves a Motrac - Low Band Even...
Large building, yes...but you wouldn't have to pay extra to heat it. ;^) - Original Message - From: skipp025 To: Repeater-Builder@yahoogroups.com Sent: Saturday, March 06, 2010 6:45 PM Subject: [Repeater-Builder] Re: Someone still loves a Motrac - Low Band Even... Is there a two way museum? Not one of any substantial size that I've ever heard about. And it would have to be a really, really large building.
Re: [Repeater-Builder] Re: 900 meg Spectra radio
Hmmm... What if someone came up with a board which could be retrofitted to a Spectra to give it ham-style programmability via front-panel controlsm, or even a separate control head? It wouldn't be interesting to the big manufacturers, but then, neither was the GLB Channelizer. 73, Paul, AE4KR - Original Message - From: rahwayflynn To: Repeater-Builder@yahoogroups.com Sent: Monday, March 01, 2010 6:00 PM Subject: [Repeater-Builder] Re: 900 meg Spectra radio $210.00 - I just bough two from KA3IDN. Search under 900Mhz Spectra on eBAY. Martin --- In Repeater-Builder@yahoogroups.com, Nate Duehr n...@... wrote: On 2/27/2010 7:54 PM, Fuggitaboutit wrote: Why cant someone just come up with a 900 meg fm mobile for amateur use? They would sell a zillion of them . What would you pay for it? Nate WY0X
Re: [Repeater-Builder] Low voltage disconnect in Alberta winters and more
Tony, What's to back up at a site already supported by both solar and wind? Is there a temp below which the PV panels won't produce or the wind turbine won't turn? Deep snow covering the PV panels? I guess my preference, for a number of reasons, would be to have a way to remotely invoke an operating mode for the repeater which could dramatically reduce standby current drain and/or transmitter power when the batteries were detected to be at any risk, or just massively bulk up on battery capacity. I had a solar powered UHF repeater in Florida once that used a 2-watt Repco RFID transmitter strip and companion receiver. Total current drain while repeating was about 700 mA. A standard 100 AH deep-cycle battery represented four days' reserve at 100% duty cycle. That would be expensive to replicate with normal repeater power levels, but maybe not as expensive as some less robust alternatives. If the PV panels get covered with snow, could you rig an automotive windshield wiper system to fire once an hour during snowstorms to keep them clear? If it's -40º, would the snow be dry and light enough to clear with a periodic blast from a cordless leaf-blower motor? The decent ones use 18-volt battery packs, but a small DC-to-DC converter could keep it charged, or switch two small 12V aux batteries charged off the main system into series, and run them through a dropping resistor to protect the motor. You'd only be running it for a few seconds at a time to keep the panels clear. What's the ground like? Could you dig deep enough to bury a battery storage locker below the frost line? Cave effect is a cheap battery temp regulator! If you're going to store fossil fuel at the site for use in protecting the batteries from freezing, what about just heating the batteries to keep them above 0ºC, and forget the moving parts involved in a generator scheme? Internal combustion engine generators are notorious for having starting problems when needed, because they sit much of the time. Interesting project and questions! 73, Paul, AE4KR - Original Message - From: Tony VE6MVP To: Repeater-Builder@yahoogroups.com Sent: Thursday, February 18, 2010 10:16 PM Subject: [Repeater-Builder] Low voltage disconnect in Alberta winters and more Folks I've been reading the low voltage disconnect thread with a great deal of interest. Thanks for the tips and suggestions. We're putting up a VHF repeater and two UHF link radios on a solar/wind power site.Given Alberta winters what would you folks suggest as a low voltage disconnect value to avoid the batteries freezing in winter? Which can hit -40 for a few days. Also we're thinking of having a backup power generator being a lawn mower motor hooked up to an auto style alternator and a rioughly eight or ten hour fuel tank.If the batteries get too low then we'll just attempt to get into the site, fire up that home made generator and walk away. We'll make sure it looks like a rusty piece of garbage so no one who wanders by is likely to steal it. Any comments? (Apparently the snow drifts can get quite bad so we might need to borrow a snowmobile for the last 400 yards or so.) We're thinking of putting the batteries in a chest freezer disguised by thin plywood so it just looks like a box. We're told by the site owner that a fridge looks way too much like trailer trash so disguising it with wood should work.I'm thinking we would put the charge controller in there for a little heat and the dump load in winter Are we nutz? Have I asked some stupid questions? Tony
Re: [Repeater-Builder] Bend an ICOM a little further
DC, he was given a free crystal which turned out to be worth what he paid. I never implied he was trying to rubber one cut for another channel, just rubber one that was too far off frequency. 73, Paul, AE4KR - Original Message - From: DCFluX To: Repeater-Builder@yahoogroups.com Sent: Wednesday, February 17, 2010 5:33 PM Subject: Re: [Repeater-Builder] Bend an ICOM a little further Seriously, some people need to read the original message before replying. The original complaint was running out of tunning range on the piston trimmer in the channel element while trying to net the crystal on frequency. Not rubbering the crystal to another channel or Nuclear warfare on an inactive club. Also I should mention that the receiver should be set by looking at the LO frequency on either a service monitor or a frequency counter of known precision, Tuning it until it sounds best is not the way to go. The LO frequency for the MASTR-II VHF will be either + or - 11.2 MHz from the receive frequency depending on the whether high side injection was specified when ordering the crystal. On Wed, Feb 17, 2010 at 3:52 PM, Paul Plack pl...@xmission.com wrote: Forgive me if I'm going where no one wants to go, but isn't there a point in the decline of a club at which the nuclear option becomes the best choice? Guys, the repeater's been a fun ride for 40 years, but we're down to three members, and no longer have enough in the treasury to keep the old girl running. The coordinator says there are people on the waiting list willing to spend the money to take care of a repeater. As I see it, we have two choices. I await your guidance. Sincerely... 73, Paul, AE4KR
Re: [Repeater-Builder] Bend an ICOM a little further
There used to be a great little company in the Toronto area called Lesmith that did a nice job with crystals at prices below ICM's. They morphed a couple times and changed names, but I think they're out of the crystal biz now. Anyone have an update? 73, Paul, AE4KR - Original Message - From: DCFluX To: Repeater-Builder@yahoogroups.com Sent: Thursday, February 18, 2010 2:20 AM Subject: Re: [Repeater-Builder] Bend an ICOM a little further I just got some Bomar crystals (Not my choice) for the clubs UHF Micor. The TX was off 14 to 39 kHz, Had to add a 10pF cap to get the trimmer in the center range. Strangely the RX was fine.
Re: [Repeater-Builder] Unlawful in Il to Rebroadcast Public Safety Communications
Don, the copy of the statute you quoted specifically exempts communications transmitted ...for the use of the general public, including Amber Alerts. What I want to know is, what if you set up across the state line with a yagi, and put it on the web from there? Your QTH would be just the place from which to do it! Nyah-nyah, Illinois! 73, Paul, AE4KR - Original Message - From: ka9qjg1 To: Repeater-Builder@yahoogroups.com Sent: Thursday, February 18, 2010 7:27 PM Subject: [Repeater-Builder] Unlawful in Il to Rebroadcast Public Safety Communications FYI It is now Against the Law in Il To Rebroadcast Public safety Communications including radio or Internet I know most of us in this Hobby are aware of all the Scanner Type Communications being linked d to the Internet. I always wondered about the legality of doing this especially living in one of the Few States that have an Anti Scanner Law against mobiles and Handhelds unless one is exempt. I always liked the idea of seeing something big on the News and finding a site from that area to listen to it Live . Well it looks like Il has put together a law against doing this I do not know about other states . Or how this is going to stop the On Line Scanner stations. Also as written unless I have permission it looks like I cannot rebroadcast the Amber Alerts which come out over My Emerg Weather Receive on My Repeaters I am sure others have this on the Repeters too This will be interesting to see if anyone is a actually charged with this Don KA9QJG Statutes Amended In Order of Appearance 20 ILCS 2615/11 new 20 ILCS 2615/12 new Synopsis As Introduced Amends the State Police Radio Act. Provides that a person receiving public safety voice or data communication transmitted via the facilities of the State's public safety radio system by wire or radio shall not, without the written authority of the originator of the communication, rebroadcast the communication via any means, including radio or Internet, or otherwise divulge or publish the existence, contents, substance, purport, effect, or meaning thereof. Provides that this provision does not apply to the public safety radio communication transmitted by any system station for the use of the general public, including Amber Alerts and other communications specifically intended for rebroadcast to the public. Provides that radio access to the public safety radio system within the State may only be accomplished upon receipt of written authorization granted by the appropriately licensed authority. Provides that a violation of these provisions is a Class A misdemeanor. Effective immediately. http://tinyurl.com/yf3on2y
Re: [Repeater-Builder] Bend an ICOM a little further
Forgive me if I'm going where no one wants to go, but isn't there a point in the decline of a club at which the nuclear option becomes the best choice? Guys, the repeater's been a fun ride for 40 years, but we're down to three members, and no longer have enough in the treasury to keep the old girl running. The coordinator says there are people on the waiting list willing to spend the money to take care of a repeater. As I see it, we have two choices. I await your guidance. Sincerely... 73, Paul, AE4KR - Original Message - From: KE4ZDG To: Repeater-Builder@yahoogroups.com Sent: Tuesday, February 16, 2010 9:57 PM Subject: [Repeater-Builder] Bend an ICOM a little further Hey folks, I'm working on a GE Mastr II high band repeater. Someone gave me some crystals that were made up for 146.010 RX. I installed one in an EC ICOM and the best I can adjust for is 146.0064, which sounds really scratchy when I inject a 3k deviation signal on 146.010. When I tune the monitor down to 146.0064, the RX audio cleans right up. I've backed out the screw until there's no more threads left in the ICOM. Is there a capacitor I can change or add to give me a little more tuning range to the ICOM? I just need the crystal to go up a hair more (400 Hz on the crystal freq). I know I'm promoting cheapness by not buying another crystal, but the club doesn't have much money to spend. Thanks, Jared
[Repeater-Builder] Ham Topics
Greg, note that while the original topic may have run its course, and has been a bit of a groaner, this list is not intended by the owners to be limited to ham repeater topics. Much of what is here by deals with comercial land moble radio repeaters. 73, Paul, AE4KR - Original Message - Hello all, I think we have heard enough pointless post about a non ham repeater topic...this is a good group of serious people used for ham radio purposes... .
Re: [Repeater-Builder] FRS/GMRS repeater urgently needed for Haiti
John, I'm not aware of any FRS radios which will operate split-frequency, so not sure how those little handhelds would be able to use a repeater. There are some FRS handhelds which will do higher power on the channels shared with GMRS, perhaps making simplex work better. Our prayers are with your worthy cause! 73, Paul, AE4KR - Original Message - From: John To: Repeater-Builder@yahoogroups.com ; repeat...@yahoogroups.com Sent: Thursday, February 11, 2010 8:27 PM Subject: [Repeater-Builder] FRS/GMRS repeater urgently needed for Haiti Hi Everyone, I'm looking for a donation of a self contained repeater for FRS/GMRS to be sent to the University of Miami Hospital in Haiti that has been setup at the airport in the capital. Does anyone have a unit that is either powered by AC or +12volts with a duplexer they would like to donate to this cause. There are about 200 doctors and nurses running around with FRS radios hanging off them that are being used to page each other in 4 different tratment tents and it is hit or miss if they get thru'. A repeater would make life much easier for them. Ideally I'd like one set up on Ch21 but will gladly take any unit that is avalable. The unit can be donated to WX4NHC, a 501 (c) 3 charity (tax-deductable, in most cases) and we'll get it to Haiti on the next flight. You might get it back when things settle down but please don't count on it We currently are operating teams of 2 hams on a wekly rotation at HH2/WX4NHC, which is running VHF and HF comms. Please, no comments about legal issues, this is an emergency and the folk in Haiti need all the help they can get at this point in time Thank you, John -- John Mc Hugh, K4AG Coordinator for Amateur Radio National Hurricane Center, WX4NHC Home page:- http://www.wx4nhc.org
Re: [Repeater-Builder] Just a Crazy Thought
My coordinator says no pairs are officially available right now, but if I marry his sister, he'll see what he can do... Seriously, CB is more than 400 kHz wide, so splits wider than the 100 kHz used on 10m would be possible. If amplitude modulation is done cleanly, sidebands could be a little tighter. I think a split-site could be done fairly easily, especially at 4 watts output. Using any licensed service as the link would probably be inviting a knock on the door. VoIP might be the deal. 73, Paul, AE4KR - Original Message - From: i recycle computers To: Repeater-Builder@yahoogroups.com Sent: Thursday, February 11, 2010 7:29 PM Subject: [Repeater-Builder] Just a Crazy Thought I have heard numorous urban legends of 27 MHz CB repeaters being built. has anyone ever come across such a thing. if not does anyone think it is even possible from a technical standpoint? .
Re: [Repeater-Builder] Re: Space-saving 6m repeater antenna?
The length of a commercial base-loaded mobile whip is nearly a full electrical 1/4-wave because the coil is there primarily to provide a convenient way to adjust impedance and run at DC ground, and leaving as much whip length as possible helps performance. If you build your own, and saving space is critical, a base-loaded antenna could be designed to be as short as needed. Whether it will disappoint later is a another matter. There have been guys who've cut down the 48 helical fiberglass CB whips to work on 6 meters with fair results. Distributing the loading along the length can sometimes work out better than putting the entire load in the base. The name brand used to be Wondershaft, but I suspect these days you'd have to look for something from Valor, maybe even shop at a truckstop. I cut one for 10m FM by carefully prying off the protective rubber tip cap, and removing a little at a time off the top with a hacksaw. The windings on the fiberglass CB whips get very close spaced right at the top, so it took only about 1/4 off the tip, IIRC, to move it 2.5 MHz, all the way up to 29.6 MHz. You might actually get all the way to 54 MHz before getting down to 1m in length, and performance may suffer if you're into the wide-spaced windings at that point. Fortunately, it would be a fairly forgiving style of antenna to cut-and-try for a homebrewer, since you could change things up before applying whatever protective coating goes on last. The CB types use an ordinary 3/8-x-24 threaded mount and are series-fed, but they're prone to static noise. If I was trying to put one on a tower, I think I'd try to leave the whip electrically short, and add at least a small coil at the base to allow shunt feeding to be at DC ground. Depending on construction, that might also allow some last-minute adjustment in impedance to match the environment, before the coil was sealed up. But then, if you're building a base coil anyway, maybe a 1m stick of aluminum tube for the vertical and a couple more turns in the base loading coil would be the better answer for durability. 73, Paul, AE4KR - Original Message - From: Chuck Kelsey To: Repeater-Builder@yahoogroups.com Sent: Wednesday, February 03, 2010 9:11 AM Subject: Re: [Repeater-Builder] Re: Space-saving 6m repeater antenna? If the length is that restricted - about 40 inches - you are probably out of luck. The ground plane is about half the length of a folded dipole, so it is actually substantially shorter. A base-loaded mobile antenna is not all that much shorter than a 1/4-wave. The one on my car is overall 50. A 1/4-wave antenna would be 54...
Re: [Repeater-Builder] On the topic of RCA radios
Um...when I click the link it opens a page with photos and a caption which says: -- RCA Corportation Model MFA02-AC21B FCC XMTR Data CT2020 FCC RCVR Data CR2003 2 channel crystal radio VHF - currently crystal in the 159.xxx range -- Are you guys with Internet Explorer not seeing it? On the bottom of the radio, someone has written both 467.750 and 159.225. 73, Paul, AE4KR - Original Message - From: k1stx To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 31, 2010 4:06 PM Subject: [Repeater-Builder] On the topic of RCA radios I have a radio that was donated to our group, and have not been able to identify the radio, to acquire information on it. Any help would be appreciated. Info and pictures at the following link: http://www.trailriding-texas.us/radio.html Thank You, Louis
Re: [Repeater-Builder] Re: UHF MSR2000 low split to ham band
UPS crooks? I'll say! A few years ago, I ordered the 220 MHz module for my Yaesu 6xx tri-bander. When it got here, I found UPS had stolen two MHz off the bottom of the band! ;^) Paul, AE4KR - Original Message - From: va...@securenet.net To: Repeater-Builder@yahoogroups.com Sent: Tuesday, January 26, 2010 12:25 PM Subject: Re: [Repeater-Builder] Re: UHF MSR2000 low split to ham band Just avoid UPS. They are crooks. Example: last year I got a yaesu combiner...
Re: [Repeater-Builder] Repeater Linking
Can you not get the cooperation of the operators of the repeaters you want to link? Without that, the technical issues will be the least of your problems. If they approve, the PL solution can actually work quite well. The decision to be part of a linked system belongs to the licensee of each repeater. A remote which allows you to use your own repeater to access another is one thing, but linking two repeaters and their communities to each other through a third-party box without approval is a no-no in my book. 73, Paul, AE4KR - Original Message - From: Jerry To: Repeater-Builder@yahoogroups.com Sent: Wednesday, January 20, 2010 4:05 PM Subject: [Repeater-Builder] Repeater Linking OK, I know I've mentioned this before, but I think I'm on to something now... I wanted to have a stand alone repeater linker, kind of a crossband repeater, that would link uhf and vhf repeaters together without needing to make any changes to either repeater. The problem I ran into is when the first repeater finishes transmitting, the linker will hear the second repeater (if the pl doesn't drop out) and will key up the first repeater again. This cycle will continue until you turn off the linker. I tried this with my crossband radio and it causes the same problem. One solution is to have the repeater controller stop transmitting their pl right after the COR drops. Not all repeaters do this, so you would have to be selective as to which repeaters you link. The solution I came up with today is to use a microcontroller with a built in a/d converter. If after the first repeater stops transmitting, the microcontroller can sample the audio coming from the second repeater. If I go through a high pass filter, I should (might) be able to determine if the audio is 'dead air', a courtesy tone, or someone talking. If it's dead air or a tone, I won't key the linker. I can then wait for the COR from the second repeater to drop, or listen for audio. Do you think it will work? - Jerry
Re: [Repeater-Builder] Re: Caution to Group Members Trojan from Yahoo Banner Advertisments
Has Yahoo been made aware? - Original Message - From: skipp025 To: Repeater-Builder@yahoogroups.com Sent: Sunday, January 17, 2010 6:27 PM Subject: [Repeater-Builder] Re: Caution to Group Members Trojan from Yahoo Banner Advertisments I actually believe I received the trojan from a banner ad while setting up new book-marks for one of the radio/repeater Groups I frequent...
Re: [Repeater-Builder] Re: Audio Mixer for multiple repeaters
Given the fact that a voter still requires an outboard repeater controller for other needed functions, and is designed to select a receiver based on S/N ratio rather than a preset hierarchy, would it really be a good choice for this application? A new LDG voter lists for $319 and still requires a separate controller. If all three receivers go active at once, it will wander between three possibly unrelated conversations based on momentary changes in S/N ratio. An SCOM 7330 is a controller with three receiver ports for $459, can be set to give each receiver a predetermined (and remotely modifiable) priority independent of S/N ratio, and would allow the three repeaters to operate independently or linked in any combination. Don't get me wrong, I've drawn up some real kluges in my day, but a voter as an audio mixer seems odd even to me. 73, Paul, AE4KR - Original Message - From: skipp025 To: Repeater-Builder@yahoogroups.com Sent: Monday, January 04, 2010 2:17 AM Subject: [Repeater-Builder] Re: Audio Mixer for multiple repeaters Each of the repeater receivers would provide audio and a cor logic to one of the eight LDG Voter inputs. You might consider the cor logic being a valid CTCSS (PL) detection, the carrier squelch COR logic or an AND version of both. There are logic enable lines on the Voter so you can turn off unwanted receivers with your external repeater controller output control lines. The output of the voter is one audio and ptt logic function, you'd have to make a simple distribution line driver amp for each repeater transmitter. You could also enable all the transmitters through simple logic we could talk you through building. To disable a repeater Transmit you'd simply supply the same receiver logic control line to disable that one transmitter. It's not that hard to build if you buy the voter. s. Gilles Violette adj...@... wrote: Hi Skipp025, How would this handle the core and the PTT audio and would it be easy to match the impedance from all the repeaters ? Thanks for the info. GVÂ From: skipp025 skipp...@... Subject: Audio Mixer for multiple repeaters Re: Audio Mixer for multiple repeaters I know it wouldn't at first glance be considered a mixer... but using an LDG Voter as a mixer (and voter) works out very well. http://www.ldgelect ronics.com/ c/252/products/ 5/19/1 If you don't need as many inputs, consider the CAT Auto RLS-1000B. http://www.catauto. com/rls1000. html And of course many repeater controllers are multi-port boxes. s. adjiqc adjiqc@ wrote: We are a club looking for an audio mixer that can mix up to 3 or 4 repeaters with different impedance, we are hooking up 3 different repeaters together. We built an homemade audio mixer but not very stable , we hope to find something solid and well shielded because there are lots of interference at that specific site. Any ideas where we could get such thing pre built or built ? Thank you
Re: [Repeater-Builder] Re: 6 Meter RF Amplifier (PA)
Oh, I dunno...if you're also paying the heat bill, running that 4-400 could be a wash! 73, Paul, AE4KR - Original Message - From: skipp025 To: Repeater-Builder@yahoogroups.com Sent: Monday, December 28, 2009 9:03 AM Subject: [Repeater-Builder] Re: 6 Meter RF Amplifier (PA) Re: 6 Meter RF Amplifier (PA) I'd love to have this PA just to tinker with... but I'd hate to be the one paying the site power bill. 6 Meter Quintron Transmitter, PA Deck Ebay Item Number: 160389525215 ... and hopefully one would not have to pay for the extra real estate (cabinet space) this baby would fill. cheers, s.
Re: [Repeater-Builder] Re: mouse debate 101
...not to mention reducing the odds of having a bear problem! As for the trash cans, anticipating human behavior can be interesting. Years ago, one of the big ham repeater sites in the southeast US actually had a few commercial tenants, which is generally a nice arrangement financially. The site had an ATV repeater equipped with multiple cameras at the site which could be switched to the repeater output. One night, during an ATV net with several dozen people watching the site-cams, the one inside caught a tech for one of the commercial tenants taking a leak out the open door of the shack. I'm not sure this guy would have taken his trash with him. 73, Paul, AE4KR - Original Message - From: Joe To: Repeater-Builder@yahoogroups.com Sent: Thursday, December 24, 2009 2:23 PM Subject: Re: [Repeater-Builder] Re: mouse debate 101 I used to have about 50 cellular sites that I maintained. One of the biggest rodent control solutions was to throw out all the trash cans at all the sites. That ended the problem of half eaten Big Macs and all other foodstuffs from being left at the site. That made a big dent in the rodent problem. With no place to throw out the garbage people usually took the trash with them. 73, Joe, K1ike
Re: [Repeater-Builder] Batteries for Backup- Methods
Bingo. My solar powered repeater developed charging issues, and when I went to check, it was due to corrosion on the homebrew charge controller's PC board. 73, Paul, AE4KR - Original Message - From: Mark To: Repeater-Builder@yahoogroups.com Sent: Tuesday, December 01, 2009 11:13 AM Subject: RE: [Repeater-Builder] Batteries for Backup- Methods Tom and all, I think I'd be more worried about corrosion issues associated with H2S gas mixing with water vapor and creating sulfuric acid (H2SO4) Mark - N9WYS From: Repeater-Builder@yahoogroups.com On Behalf Of Chris Quirk Well boats usually do not blow up or catch fire from hydorgen leaking from batteries. It is usually from gasoline vapors or leaking propane. The plastic battery box is a corrosion / spill containment issue. . You add to this that hydrogen rises very quickly as it is much lighter than air and you ask the question how much gas would stay in an enclosed area ? My guess is little to none. --- On Mon, 11/30/09, TGundo 2003 tgundo2...@yahoo.com wrote:30, 2009, 3:35 PM Thanks to everyone for the feedback so far!
[Repeater-Builder] Acceptable RB Religious Discussions
Guys, please...the only sanctioned religious discussion on this board is Motorola vs GE. 73, Paul, AE4KR
Re: [Repeater-Builder] ACSSB
I find nothing in Part 97 which would preclude ACSSB, as it appears to meet the definition of phone, but I do recall some debate at the time on whether the audio frequency inversion scheme/pilot tone was a form of scrambling/encryption, which would have made it illegal on the ham bands. The main benefit of that inversion was to preserve low-frequency audio response which normally is tough with a filter-based SSB exciter, and put the pilot tone at a frequency where it was easily processed and filtered, but hams are accustomed to narrow audio bandwidths and ducks talking, and there was no compelling reason to play with ACSSB. To some extent, ACSSB was simply the worst of all worlds, like NBFM with more ignition noise and companding artifacts, or SSB but restricted to channels. It made sense on paper as an analog bandwidth conservation tool compared to NBFM, but sounded really bad in areas of marginal signal, and who's still developing analog techniques these days? One reason for lack of interest in the mode I haven't seen mentioned was the incredible hostility generated among hams by the taking of 40% of the 220 MHz band to make commercial ACSSB happen. Just the mention of ACSSB at a club meeting would result in spontaneous aneurisms, even among hams who'd never operated on 220. Nobody wanted to be associated with ACSSB. We were too busy boycotting UPS! 73, Paul, AE4KR - Original Message - From: n0fpe To: Repeater-Builder@yahoogroups.com Sent: Thursday, November 12, 2009 5:34 AM Subject: [Repeater-Builder] ACSSB One thing to remember. Amatuers are NOT authorized to use ACSSB above 30mhz. Please check part 97 for the exact modes we are able to use. heck if we were there would be tons of ACSSB repeaters already modified into the ham band.
Re: [Repeater-Builder] PGE Smart Meter Program
Sounds to me like having a friend in the shop at PGE will come in handy when it's time to build short-hop links or a portable event repeater! - 73, Paul AE4KR - Original Message - From: skipp025 To: Repeater-Builder@yahoogroups.com Sent: Wednesday, November 11, 2009 11:02 AM Subject: [Repeater-Builder] PGE Smart Meter Program For those of us out here on the West (Left) Coast... PGE our Electricity Provider has started their Smart Meter program, where the meter reading will now be done by RF Communications. I had concerns about the equipment causing interference so I called and received the following information. RF Frequency Range of operation 450-470 MHz FSK Modulation Power Out - reported 100 to 300 mW, 200mW typical. Reporting Time - once every 4 to 6 hours. Who's going to pay for it... you the customer. cheers, s.
Re: [Repeater-Builder] Repeater Bells and Whistles (from an off group source)
I recall the repeaters of the ACC era, how the overused bells and whistles were viewed as advanced, and how so many repeaters coast-to-coast had no individual personalities, only those same canned TI voices and LOUD three-tone courtesy beeps. I also recall how funny it was to hear the male and female robots programmed to argue with each other...until about the 100th play. Digital voice recordings are much nicer to hear than the 'bots, and can reflect local accents and character, but I shake my head every time I hear an inattentive CQ-er start a conversation with the automated ID playback. I love the notion of the courtesy beep as a diagnostic tool, provided it doesn't distract from the content of the traffic. When I was working on repeaters for the Blue Ridge Amateur Radio Society in the Carolinas in the '80s, we were transitioning to CTCSS, but ran the Paris Mountain repeater in carrier-squelch mode except during periods of interference. Because users were trying everything from actual PL reeds to 555 chips as encoders, I programed the SCOM 6K to reverse the high-to-low courtesy beep on transmissions with correctly decoded tones, so users would know if their tones were good even during periods of carrier access. It was subtle, but if you were listening for it, you could easily hear the difference. (I tried to approximate the in-band cue signals used on the old Mutual Broadcast Network, a very distinctive, but low-level bee-doop.) One member apparently didn't read the club newsletter to know about the feature, but noticed one day on the air that he had a high-low beep, while the members of the tech committee had the opposite, low-to-high pitch. He asked why it was different. My partner on the committee told him the repeater knows who daddy is. I was less charitable...I told him it was an IQ detector. I like hearing a Morse letter as a courtesy beep to identify which of the voted receivers or linked repeaters was just heard, provided they're quick and not too loud. Beyond that, except for ancillary functions which can be requested by a user for just that moment, and perhaps an unsolicited readback to identify a serious techical deficiency with a signal just heard, I'm a fan of less is more. 73, Paul, AE4KR - Original Message - From: skipp025 To: Repeater-Builder@yahoogroups.com Sent: Tuesday, November 03, 2009 10:46 AM Subject: [Repeater-Builder] Repeater Bells and Whistles (from an off group source) In my repeater days I went both ways. Started by wanting to add anything that showed the repeater to be more advanced. We had custom-recorded audio IDs, and at one point, over 500 repeaterisms - semi-humourous statements read in any of several celebrity voices... .
Re: [Repeater-Builder] Re: Weird Interference between APRS and 2-M repeater help needed
Can you receive through a circulator without heavy losses? I've never tried it... - Original Message - From: David To: Repeater-Builder@yahoogroups.com Sent: Monday, November 02, 2009 1:31 PM Subject: [Repeater-Builder] Re: Weird Interference between APRS and 2-M repeater help needed First of all you do not have enough isolation between antennas with only two wavelenghts horizonal seperation. A single bandpass cavity will not be enough. I would try 2 bandpass/bandreject cavities. Reject set for the TX freq and the other set for the RX freq. I believe that RF from your repeater is exciting the RF amp in your aprs tranceiver, see if the problem is still present with the aprs hooked up to the antenna but with your power supply disconnected. Most people used a simple mobile for aprs which creates alot of headaches where several transmitters are used. They just dont have the filtering needed for this application. You should also use a circulator on your aprs radio. This will help keep RF out of your aprs transmitter. David Epley, N9CZV Winchester, In .
Re: [Repeater-Builder] Re: Weird Interference between APRS and 2-M repeater help needed
I guess there are some sites noisy enough that losing 30 dB wouldn't affect S/N... ;^) - Original Message - From: skipp025 To: Repeater-Builder@yahoogroups.com Sent: Monday, November 02, 2009 4:29 PM Subject: [Repeater-Builder] Re: Weird Interference between APRS and 2-M repeater help needed I do it all the time in a test jig to set up mobile vehicle repeaters. Helps protect the non power term ports of a Service Monitor. You'd be surprised how much you can hear through it... s. Paul Plack pl...@... wrote: Can you receive through a Circulator without heavy losses? I've never tried it... .
Re: [Repeater-Builder] Pager Interference to 2-meter VHF Public Service Band
Mike, If it moves around based on time of day, my first guess is a PA that's gone bad, and has a parasitic that's temperature-related. If you've tracked an individual spur drifting 70 kHz up the band during a single transmission, this is not some (intentional) oscillator drifting, but some combination of failed components or tuning which has produced a parasitic. Sorry to say, but a paging transmitter owner swearing his stuff is clean is pretty meaningless. The assumption in his industry is the professionals who maintain his stuff are not the problem, it's those damn hams. Sadly, it may more often be the other way around these days, as companies maintaining paging equipment have transitioned to underpaid, under-trained card-swappers instead of component-level technicians with a clue about RF systems. 73, Paul, AE4KR - Original Message - From: Mike To: Repeater-Builder@yahoogroups.com Sent: Wednesday, October 28, 2009 12:28 PM Subject: [Repeater-Builder] Pager Interference to 2-meter VHF Public Service Band A couple of weeks ago, our repeater system started to experience interference from a paging system... ...one evening I tracked it from about 145.120 to 145.190 as it swept through each transmission... .
Re: [Repeater-Builder] Pager Interference to 2-meter VHF Public Service Band
Mike, the interference is clearly not caused by your own rusty roof, and is both eggregious and easily documented. I know we hate to go there unless it's a last resort, but I'll bet the FCC is almost as tired of non-compliant pager systems as we are. Perhaps that technique would prove motivating. - Original Message - From: Mike Besemer (WM4B) To: Repeater-Builder@yahoogroups.com Sent: Wednesday, October 28, 2009 5:34 PM Subject: RE: [Repeater-Builder] Pager Interference to 2-meter VHF Public Service Band I'm with ya on your third paragraph. We've worked well together so far, but we have very different techniques and motivations... .
Re: [Repeater-Builder] MICOR Squelch clones
You guys have talked past each other slightly... Kevin, if he's not using straight discriminator audio into the controller, but picking off de-emph audio downstream from the Kendecom squelch gate, there will be times he has COS from the Micor module but no audio reaching the controller. Workarounds might include: (1) Leave the original squelch control open (2) Tap and buffer discriminator audio using a discreet or LM386 stage with R/C filter to provide unsquelched but de-emph audio for the controller (3) Use the COS signal from the Micor module to both provide COS to the controller and switch the Kendecom's audio gate I'd try for (3). 73, Paul, AE4KR - Original Message - From: Kevin Custer To: Repeater-Builder@yahoogroups.com Sent: Friday, October 23, 2009 8:03 AM Subject: Re: [Repeater-Builder] MICOR Squelch clones Kevin, Don't I have to disable the existing squelch circuit as well to prevent it from muting the RX? Mike Yes, that will be done when you connect the logic of the new squelch board to drive the controllers COS. Only the COS from the MICOR board should be connected to the controllers COS input, replacing the original COS logic from the receiver. Some controllers require a presence of voltage to validate activity on the channel, some require a ground. The Link-Comm MICOR squelch board (RLC-MOT) will supply either logic polarity, making installation easy. Kevin .
Re: [Repeater-Builder] Re: Audio Delay
John, I experimented with that once, and in some situations, it's the most elegant way to derive a COS-like logic signal from an audio stream that doesn't carry imbedded switching info. A fast, stable VOX gate listening to the output of a squelched radio receiver can provide a very useful switching signal. Set the VOX threshhold to a point where it ignores the quiescent noise level of the squelched receiver, but triggers reliably on any trace of CTCSS tone or ambient noise behind the party transmitting, and set the VOX delay to zero. Because it doesn't care about frequency, it can actually act more quickly than a PLL CTCSS decoder, especially on the lower tones. 73, Paul, AE4KR - Original Message - From: JOHN MACKEY To: Repeater-Builder@yahoogroups.com Sent: Friday, October 23, 2009 2:45 PM Subject: Re: [Repeater-Builder] Re: Audio Delay WHY would someone be using VOX in a system linked to a repeater (such as Echolink)? -- Original Message -- Received: Fri, 23 Oct 2009 12:49:01 PM PDT From: skipp025 skipp...@yahoo.com To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: Audio Delay SNIP Helping my echolink node not get confused about what it is supposed to listen to is my primary purpose for having the delay. Audio delay lines are killer (great) for use with VOX (voice) operated logic... and a must have for many simulcast transmission packages.
Re: [Repeater-Builder] Re: Astron Power Supply Alert
Tom, I'm also a very satisfied Astron user. People whine, but there's nothing like them at their price point. My comment wasn't about the esthetics or hipness of the Yahoo address, but its functionality. They work OK most of the time, but so much illicit stuff is done through disposable e-mail addresses at Yahoo, MSN, Hotmail, etc. that there are times when the inter-ISP blacklist services block them for hours at a time, and the account holder doesn't even know some of his customers are unable to reach his inbox. 73, Paul, AE4KR - Original Message - From: wb6dgn To: Repeater-Builder@yahoogroups.com Sent: Wednesday, October 21, 2009 11:14 PM Subject: [Repeater-Builder] Re: Astron Power Supply Alert Nothing says we're reputable and here to stay like a company e-mail address at yahoo.com! I think I'd find a more reliable way to evaluate a company than the email address they use. Not everyone considers an email address all that important... .
Re: [Repeater-Builder] Re: Astron Power Supply Alert
LOL! Nothing says we're reputable and here to stay like a company e-mail address at yahoo.com! Nothing against the power supplies, miy 1995-vintage RS35 still works fine, but sheesh! 73, Paul AE4KR - Original Message - From: WA Brown To: Repeater-Builder@yahoogroups.com Sent: Tuesday, October 20, 2009 10:00 PM Subject: Re: [Repeater-Builder] Re: Astron Power Supply Alert What is wrong with the power supply? Here is the contact info for Astron. 9 Autry, Irvine, CA 92618 949-458-7277 . FAX:949-458-0826 E-MAIL: astroncorporat...@yahoo.com .
Re: [Repeater-Builder] Re: kendecom repeaters on 220
On the transmitter page, ACS says, all our products are rated for continuous commercial duty. Then, a little lower, 90% DUTY CYCLE Do they even know? 73, Paul, AE4KR - Original Message - From: skipp025 To: Repeater-Builder@yahoogroups.com Sent: Monday, October 19, 2009 9:37 AM Subject: [Repeater-Builder] Re: kendecom repeaters on 220 I gotta laugh at their web pages a bit... http://www.advcommsys.com/mr4receiver.html http://www.advcommsys.com/mt4transmitter.html .
Re: [Repeater-Builder] Re: kendecom repeaters on 220
Now Skipp, they're obviously protecting some very impressive technology. Look down the specs...their high-power 2m transmitter does 30 watts out while drawing only 500 mA at 24V. I don't care where you live...250% efficiency, including all stages, is impressive! ;^) 73, Paul, AE4KR - Original Message - From: skipp025 To: Repeater-Builder@yahoogroups.com Sent: Monday, October 19, 2009 9:37 AM Subject: [Repeater-Builder] Re: kendecom repeaters on 220 I gotta laugh at their web pages a bit... http://www.advcommsys.com/mr4receiver.html http://www.advcommsys.com/mt4transmitter.html Lots of pictures of the outside of boxes but no internal circuit board views. Why can't we see what's under the hood? .
Re: [Repeater-Builder] Maybe a strange question...
Randy, it's pretty common these days for a transceiver in a valley to have much higher useful sensitivity than a receiver at a high repeater site, because your noise floor may be much lower, and the front end of the repeater's receiver may require much higher selectivity. It is also possible that the other repeater is running above its coordinated power level. I believe that many are. Such an accusation is usually unproductive. If you can still hear your own repeater over the distant one when both are active, that is NOT interference, that's users whining. CTCSS works both ways. Put it on your repeater's output, have users use decoders on their receivers, and *-poof-* problem solved. 73, Paul, AE4KR - Original Message - From: Randy Ross To: Repeater-Builder@yahoogroups.com Sent: Thursday, October 15, 2009 7:04 PM Subject: [Repeater-Builder] Maybe a strange question... If all else is the same, I should be able to bring the repeater up. Or, is this repeater putting out much more than 55w ERP? .
Re: [Repeater-Builder] Help, please.
Eric, right off, I'll challenge the assumption that you need 25 miles separation. You'll have too many users who can her the output but not get in, and vice versa. A mile or two should be plenty. Linking via the internet can be done, but making a ham repeater reliant on two internet connections is controversial. Is the transmitter on that Midland capable of 100% duty cycle? Most mobiles are not. 73, Paul, AE4KR - Original Message - From: Eric Mynes To: Repeater-Builder@yahoogroups.com Sent: Friday, October 09, 2009 10:43 PM Subject: [Repeater-Builder] Help, please. Greetings all, I joined this group because since earning my license I've wanted to set up... .
Re: [Repeater-Builder] Question on portable repeaters
Peter, I haven't seen this mentioned, but perhaps you could do a split-site repeater, with a 2m rcvr, basic controller, low-power UHF transmitter and small solar panel ready to hang on a utility pole somewhere, then park the SUV with a UHF link receiver and 2m transmitter a half-mile away but line-of-site. More pieces, a little tougher to set up, but much more compact than using a 2m duplexer. It's hard to beat 440 for a mobile or portable repeater. Tiny duplexers work, surplus commercial gear is cheap and plentiful, and many hams have radios for it. The repeater part is easy on 900 MHz and 1.2 GHz, but almost nobody has radios for those bands outside a couple big cities. 73, Paul, AE4KR - Original Message - From: Peter Dakota Summerhawk To: Repeater-Builder@yahoogroups.com Sent: Wednesday, October 07, 2009 5:15 PM Subject: [Repeater-Builder] Question on portable repeaters Morning, We are looking at building a portable repeater for special even use. This will be mobile mounted and 2M. My questions is this: If we are using two radios (one for TX one for RX) then what does the antenna separation have to be for all of this to work? Planning on mounting this in a SUV so roof space can be adjusted if need be. Thanks Peter Dakota Summerhawk Laramie County ARES
Re: [Repeater-Builder] UHF Duplexers
If you just can't get access to a VNA and someone who knows how to use it, having a 50-ohm attenuator on hand to put between the duplexer and the handheld or mobile rig can help a great deal. They can be found with BNC connectors on hamfest junk tables, (make sure they're 50 ohms,) or homebrewed fairly easily as long as you're careful with shielding. A 6-dB or 10 dB pad will still pass all the signal you need from the generator. - Original Message - From: Eric Lemmon To: Repeater-Builder@yahoogroups.com Sent: Sunday, September 20, 2009 10:25 AM Subject: RE: [Repeater-Builder] UHF Duplexers The most obvious problem when using a handheld radio is that the antenna connection on a handheld is very seldom optimized at 50 ohms...a VNA has precise 50 ohm matches on all ports... .
Re: [Repeater-Builder] New articles
Mike, great primers, all. Only squawk I'd have is, in the doesn't fix anything article, where the reader is referred to Historical and Technical Overview, make the title a link to the other article. I've also abandoned underlining text for emphasis in HTML documents, since most new visitors will think its a link, and use bold, italic or highlighting instead, but if RB has many documents using the underlining convention, I guess there wouldn't be much point. 73, Paul, AE4KR - Original Message - From: Mike Morris WA6ILQ To: Repeater-Builder@yahoogroups.com Sent: Monday, September 21, 2009 4:43 PM Subject: [Repeater-Builder] New articles I've had a lot of support on my question about an old PL tone list, and several private emails back and forth. I'd like to thank those that helped, and invite comments from all. .
Re: [Repeater-Builder] HF Remote Bases - Illegal?
Assuming manufacturers will limit the capabilities of their equipment to the letter of the Part 97 law has proven unreliable. Manufacturers of imported dual-band mobiles provided capability for aux operation using 2m as the control side years before it was legal, and lots of ACC-controlled 2m repeaters were used as remote bases back when aux operation was limited to 220 and up. I also recall the whole control debate that led the FCC to create the term ancillary function to distinguish an autopatch from a signal disabling a transmitter, etc. I have at times been frustrated by limits designed into ham equipment by Part-97-observant manufacturers who did not anticipate some adaptations which would have repurposed their boxes for unusual, but legal functions. 73, Paul, AE4KR - Original Message - From: larryjspamme...@teleport.com To: Repeater-Builder@yahoogroups.com Sent: Friday, September 04, 2009 10:43 AM Subject: [Repeater-Builder] HF Remote Bases - Illegal? There's a discussion on the list about how HF Remote Base stations are most likely not legal. Trying to reason with some of these people is an excercise in futility. But if that was the case, why do almost all new higher-end Repeater Controllers (and even some of the older 1980's controllers like the ACC RC-85 and SM-100 ShackMaster, AEA Radio Link unit, etc.) have direct control of various HF transceivers' capability? .
Re: [Repeater-Builder] Repeater trouble
I heard a similar problem with an ARES net in Oregon. One of the county EOC's had installed a high rooftop antenna for the hams, and could be worked on simplex for many miles, but into the main ARES 2m repeater it sounded as you described, to the point it was unintelligible. It was fine into other repeaters, and the same operator could switch to a simple J-pole or ground plane on a balcony railing and be perfect into the ARES repeater. My best guess is the antenna, which was on a rooftop bristling with other antennas, was in some unfortunate spacial relationship to other conductors to produce a really disruptive multipath signal on the specific compass heading of the repeater used for the ARES net. The good news: the fix would be simple. The bad news: it would also be a major PITA. You may have to go to that remote site and move something 4 inches to get it to work. 73, Paul, AE4KR - Original Message - From: John Sehring To: Repeater-Builder@yahoogroups.com Sent: Wednesday, September 02, 2009 12:35 PM Subject: [Repeater-Builder] Repeater trouble Hi all, We have a puzzling problem with our two 2m repeater networks. They all use Mitrek's on 2m and Maxtrac's on UHF for linking; each network has a handful of satellite repeaters, all on diff. 2m freqs of course. All satellites use one of two UHF freqs for simplex linking to their hub repeaters. All it takes to swing a satellite repeater from one network to another is to change the UHF link freq. With the Maxtrac's, that's easy (or should be!). In one instance, we've struggled greatly to do this successfully. After reprogramming the Maxtrac at the repeater site, the UHF linking signal sounds fine on HT's, dual band transceivers a consumer-grade scanner _at the remote site_. But from the hub repeater, the VHF output signal, coming in from this newly-linked repeater ONLY, sounds garbly, like AC ripple or overdriven PL tone (we don't use PL). At the linked repeater site, we've changed antennas, power supplies link Maxtrac with no improvement. As our repeater sites are rather remote (in the middle of nowhere, hours driving away from one another, and/or up mountain peaks), we've not had a chance to listen to it at the hub site. So we don't know if the UHF signal is arriving there ok or not, or whether the VHF output signal is somehow being corrupted. The puzzling thing is that A) the newly linked repeater worked perfectly with the 2nd network and B) all satellite repeaters use the same UHF link freq they all work FB. I wonder what we're missing (duh!)? Any thoughts? Thanks! --John WB0EQ/VE6
Re: [Repeater-Builder] Diversity FM reception
Lots of consumer TV receivers use vertical, telescopic whips. - Original Message - From: larynl2 To: Repeater-Builder@yahoogroups.com Sent: Monday, August 24, 2009 4:23 PM Subject: Re: [Repeater-Builder] Diversity FM reception The local channel 8 analog station here had a CP antenna. To get their 316KW horizontal ERP they put 77KW up the coax from a many-yards-long Larcan transmitter. They had a whopper signal around here and it was very easy to get a great picture even with rabbit ears. I know that their excellent signal wasn't just because of CP, but it had to help. I wonder what their reasons were to go CP? Laryn K8TVZ . ,_._,___
Re: [Repeater-Builder] Squelch action on 10 m FM
John, how's this for an experiment... Configure a repeater with two receivers, one built for +/- 5 kHz deviation, the other for +/- 15, feed them from a splitter, use audio from the narrow one, but allow a DTMF command to select the wider receiver's COS when conditions warrant. (Obviously, those conditions would have to include no adjacent channel signal...) Or, four receivers...I've always wanted to play with H/V polarization diversity when the band was up! ;^) 73, Paul, AE4KR - Original Message - From: John Sehring To: Repeater-Builder@yahoogroups.com Sent: Thursday, August 20, 2009 4:36 PM Subject: [Repeater-Builder] Squelch action on 10 m FM BTW, the less the deviation, the harder it is to design reliable squelch circuits. It was easier in the +-15 kHz deviation daze. The supersonic audio spectrum will be different for other tx deviation/rx IF bandwidth situations... .
Re: [Repeater-Builder] Diversity FM reception
When I lived in Atlanta in the 80's I was a few miles from the local 10m repeater, and quickly noticed that distant stations which were fading on the repeater input had climbing signal strength at my location if I switched to the input. About the time they started getting ratty at my place, I could switch back to the repeater output, and they were solid there. I think, on 10m, voting receivers separated by a few miles could actually be of greater help for maintaining communications with distant stations than for local mobiles. 73, Paul, AE4KR - Original Message - From: John Sehring To: Repeater-Builder@yahoogroups.com Sent: Friday, August 21, 2009 11:11 AM Subject: [Repeater-Builder] Diversity FM reception Paul, I use double or even triple diversity on 10m 6m FM. On 10m, I use a base-fed half-wave vertical installed right above on the same mast as a 3-ele horizontally polarized 10m beam. That gives me rather more polarization than space diversity but it works FB. I have a 3rd identical rx as well, feed that with an HF longwire ATU. One in a while, I get 2 different QSO's from the two rx's! What with FM rx capture effect (typically 6-8 dB), if one signal is 6-8 dB stronger on one receiver another sig is 6-8 dB stronger on the other rx, that's what happens... .
Re: [Repeater-Builder] Re: Squelch action on 10 m FM
Perhaps one the remaining contributions we could make as amateurs would be working with DSP to combine all these attributes in a standalone uP module. It would be great to have an adaptive squelch board for retrofit into repeaters which could account for multipath, propagation conditions, noise levels, and user priorities. It will probably fall to us to do it, because we'll no doubt be the last users of analog NBFM. Besides...those Micor squelch chips won't last forever! 73, Paul, AE4KR - Original Message - From: ka1jfy To: Repeater-Builder@yahoogroups.com Sent: Friday, August 21, 2009 5:16 PM Subject: [Repeater-Builder] Re: Squelch action on 10 m FM Because CTCSS falses on the random noise. Been there, done that, gave away the t-shirt. WalterH --- In Repeater-Builder@yahoogroups.com, n...@... wrote: At 8/20/2009 23:17, you wrote: John, how's this for an experiment... Configure a repeater with two receivers, one built for +/- 5 kHz deviation, the other for +/- 15, feed them from a splitter, use audio from the narrow one, but allow a DTMF command to select the wider receiver's COS when conditions warrant. (Obviously, those conditions would have to include no adjacent channel signal...) If noise squelch is so problematic in severe multipath conditions, why not do away with it entirely use straight CTCSS squelch? The GE decoders that use Versatone chips are fast enough that you can still almost eliminate the squelch tail with an ADM. Bob NO6B
Re: [Repeater-Builder] ENHANCED RECEIVE
Artie, not sure I can picture the block diagram, but it's common to use a cavity or attenuator between the preamp and the receiver front end to avoid overload. 73, Paul, AE4KR - Original Message - From: k2aau To: Repeater-Builder@yahoogroups.com Sent: Tuesday, August 18, 2009 8:47 PM Subject: [Repeater-Builder] ENHANCED RECEIVE I have heard of repeater owners using pre-amps on the receive side of the duplexer and adding 1 pass-reject cavity after the preamp and placing a pre-amp on the pass reject cavity to enhance more receive. Does this work or is it a myth? Artie k2aau
Re: [Repeater-Builder] Re: An advocate for a little audio compression
No, John, I was never been a CE, but a PD several times. This same guy was the first to have on his door a sign I've since seen several other places: Procrastination on Your Part Does Not Constitute An Emergency on My Part 73, Paul, AE4KR - Original Message - From: JOHN MACKEY To: Repeater-Builder@yahoogroups.com Sent: Sunday, August 16, 2009 2:00 AM Subject: Re: [Repeater-Builder] Re: An advocate for a little audio compression Apparently you are one of the former Chief Engineers at the station I am currently the engineer of! -- Original Message -- Received: Sat, 15 Aug 2009 10:36:11 AM PDT From: Paul Plack pl...@xmission.com In my years in broadcast radio, I often saw program directors and general managers who wanted engineering to alter equipment to accommodate some prima donna morning talent too lazy to exercise proper mic technique or maintain proper levels. One particularly brave chief engineer responded, I'm sorry, this is engineering. You're describing a human resources problem.
Re: [Repeater-Builder] Re: An advocate for a little audio compression
It's no more closed than a repeater with CTCSS or even a tight squelch, but what a pain in the butt for users with equipment set properly! You hear the repeater drop, wait for the beep, and then are doubling with someone? That's a solution? This sounds like the work of a passive-aggressive type who'd rather automate the punishment than offer help. Most people coming into the hobby today come from a world of horrid bluetooth headsets and auto record levels, and have never seen a VU meter. What? It matters how loud or close I am? In my years in broadcast radio, I often saw program directors and general managers who wanted engineering to alter equipment to accommodate some prima donna morning talent too lazy to exercise proper mic technique or maintain proper levels. One particularly brave chief engineer responded, I'm sorry, this is engineering. You're describing a human resources problem. I always thought it might be useful to record a local ARES net, edit excerpts of people with really bad audio, and make them available as MP3 files on a website afterward. You can tell someone his audio is so low you can't understand him, but until he hears it, he may think you're just picky. 73, Paul, AE4KR - Original Message - From: ae6zm To: Repeater-Builder@yahoogroups.com Sent: Friday, August 14, 2009 6:54 PM Subject: [Repeater-Builder] Re: An advocate for a little audio compression Sounds like, in essence, it was a closed repeater. Only those meeting some tough standards were allowed. Nothing wrong with that, as long as one doesn't call it an OPEN repeater. OPEN being anyone operating within the limits of the FCC rules is welcome. It would be ANDed with the COS, so that anyone too soft-spoken would drop out of the repeater. We had one repeater around here with that feature. AFAIK it worked quite well. .
Re: [Repeater-Builder] Re: 2M Vertical Dipoles
If you mount the array on a non-conductive pole, won't you then have to model the effects of interaction with the outside of the coax shields of the feedline harness that would normally be insignificant when attached to the side of a conductive pole? - Original Message - From: AJ To: Repeater-Builder@yahoogroups.com Sent: Monday, August 10, 2009 9:27 AM Subject: Re: [Repeater-Builder] Re: 2M Vertical Dipoles On this same topic of the mast-less Antennex/Laird dipole arrays, has anyone attempted to top mount these from a fiberglass mast to minimize interaction with the normal steel pole? I have quite a few surplus fiberglass poles left that would likely work, even for side mounting on 1/2 wave spacing from the tower...
Re: [Repeater-Builder] An advocate for a little audio compression
Skipp, I generally agree, but it's not the fault of the user's voice. It's a lack of training in mic technique, sometimes combined with audio circuits that aren't easily user-accessible. Compression on the repeater eliminate's the user's need to get things right at the source, and one day, he's going to need to operate simplex. I've worked with broadcast compressors for many years, and agree they could play a useful role in repeater audio chains. But I always wanted to design one that was a little different, and digital control of an analog signal path seems like a good candidate. Specifically, I'd like to have something like a compressor with very fast attack and infinitely long release, immediately dropping gain as needed to accommodate voice peaks, but not releasing until COS dropped. This would essentially set the audio gain individually for each user at the start of a transmission, without any ongoing compression to create the obnoxious pumping artifact we all know and hate. The downsides would be additional background noise before the first syllable, and difficulty in distinguishing users with low audio from users with inadequate signal strength. Both would feature increased background noise as a symptom. Then again, IRLP users hand out S-meter reports from a thousand miles away, so maybe it doesn't matter...(sigh) Just running the audio gain 6-10 dB hotter into a fast limiter still allows great disparity in perceived loudness, but at least the guys with low audio can be heard. 73, Paul, AE4KR - Original Message - From: skipp025 To: Repeater-Builder@yahoogroups.com Sent: Sunday, August 09, 2009 9:07 PM Subject: [Repeater-Builder] An advocate for a little audio compression ...a number of operators don't seem to have voices that drive their radios with adequate audio...Consider 6 to 10dB of audio compression in your repeater system... .
Re: [Repeater-Builder] Re: GMRS HT recommendation?
Walter, Part 15 covers unlicensed operation. As a ham, you're licensed under the terms of Part 97, which has specific rules for emissions types and purity. (97.305 and 97.307 in particular.) If you buy a commercial product not already certified to comply, and were ever accused of, say, spurious tranmitter radiation, you would need to be able to demonstrate to the FCC the means you used to determine its compliance, just as with homebrew gear. The test equipment needed is not in most hamshacks these days. But it could be done. A really confusing development in recent years is ham equipment which has come with Part 15 stickers on it. I have to assume that the stickers were a well-meaning attempt by manufacturers to cover their butts regarding the microprocessors used in running modern gear, and not the 10 mW cloning signals, since Part 15 operation is not authorized in the ham bands, regardless how low the power. 73, Paul, AE4KR - Original Message - From: Cort Buffington To: Repeater-Builder@yahoogroups.com Sent: Saturday, August 08, 2009 8:38 AM Subject: Re: [Repeater-Builder] Re: GMRS HT recommendation? Here's a question I've not been sure about: If a radio isn't Part 15 registered, is it even legal for ham use? If we build our own or heavily modify, that's one thing, but I think if it's a commercial product, it still has to meet FCC Part 15 doesn't it? .
Re: [Repeater-Builder] OT: Suicom 2 way radio Transceiver recall - Ouch!
I wonder if this is a battery issue, possibly affecting any user, or simply a handheld that was supposed to be rated for use in explosive environments which turns out not to meet spec. In any event, a very funny recall notice! 73, Paul, AE4KR - Original Message - From: ks4ec To: Repeater-Builder@yahoogroups.com Sent: Thursday, August 06, 2009 2:55 PM Subject: [Repeater-Builder] OT: Suicom 2 way radio Transceiver recall - Ouch! This was clipped from the web site http://indonetwork.net/suicom2way_radio/1486669/ct-08-recall.htm CT-08 RECALL NOTICE Due to fault of design and distractor of components when manufacturing, the CT-08 will probably cause explosion while operating. The possibility is very high. Sorry for any inconvenience caused. DOH! But they will give you 4x what you paid for it!
Re: [Repeater-Builder] OT: Suicom 2 way radio Transceiver recall - Ouch!
But then...how did they make it through quality assurance? Oh, wait... - Original Message - From: DCFluX To: Repeater-Builder@yahoogroups.com Sent: Thursday, August 06, 2009 3:32 PM Subject: Re: [Repeater-Builder] OT: Suicom 2 way radio Transceiver recall - Ouch! If I'd have to guess I'd say certain components, like polarized electrolytic capacitors are installed backwards on the board.
Re: [Repeater-Builder] Portable repeater
Allen, I'll echo the comments of those who've said 2m is not the best choice for a portable repeater, due to the required close frequency spacing. A 440 MHz repeater solves a number of problems regarding duplex operation. I built a solar-powered repeater a few years ago, and had to operate it on a very limited power budget. After looking at options, I used a Repco 2-watt UHF transmitter sourced from an RFID application, and a companion receiver. The transmitter drew only 650 mA at 1.8 watts output, and the receiver only another 22 mA in squelched standby. The controller was the most inefficient part of the package, drawing 100 mA continuous. Still, I had four days' reserve battery power even if the solar panel failed, assuming 100% duty cycle, using a group-27-sized deep-cycle marine battery, which was rated at 105 amp hours. If I had your needs, I'd do something similar, but using a much more power-efficient controller. This would allow using a much smaller battery. SAR outings often don't last more than a few days, so solar charging might not even be necessary, especially if you could occasionally visit the repeater site with a vehicle to recharge the battery. Also look into the options for small-scale wind turbines. There are mast-mount generators available in the recreational vehicle market that would easily hold up a small repeater in heavy use. They look a little pricey, and not terribly durable, but for this application they'd be great. When looking for a transmitter, do your homework to find one which is efficient at the power level you want. Most transmitters become very inefficient when run below their rated max output. Choose one that's running full-bore at the power level you need - it will use less current and dump less heat than a larger transmitter dialed back. Some small crystal-controlled receivers have very low current drain compared to their synthesized equivalents. Regarding control, there may be locations at which CTCSS access will save more battery current than the decoder draws. Especially if you're in the midst of a bunch of public service agencies running enough power to overload your receiver's front end, you're transmitter may stay up way more than it should. If you really must use 2m, my first choice would be to modify a pair of dual-band, full-duplex-capable handhelds to make a split-site repeater using a UHF link frequency. The receive site wouldn't take much in the way of mods...find a way to add a simple controller, and run low power with CTCSS or DCS on the UHF transmit. The other end would need some sort of external heatsink, and might need building a new enclosure for the radio, but you could have 2-5 watts continuous if you needed it. Separate the sites by a half-mile or more, and you're there. But UHF would be much cleaner, and faster and easier to set up. 73, Paul, AE4KR - Original Message - From: vhsproducts To: Repeater-Builder@yahoogroups.com Sent: Monday, August 03, 2009 11:09 PM Subject: [Repeater-Builder] Portable repeater I am in the design stages for a portable VHF (2 meter ham) repeater, and thought I would solicit the views of the group for desired features. In broad strokes, we plan on a computer programmable unit, capable of one or two field selectable operation modes. CTCSS only, no COS or DTS. This is primarily to support our SAR users (I manufacture the Micro-Trak line of APRS tracking systems sold by Byonics-www.byonics.com) We will have DTMF remote control. The goal is a bare-bones repeater, with no provision for a duplexer, so wide channel separation and physically separate antennas will be a must. Battery power will be the norm, and I am thinking of a system with no more than 8 Watts output. What features are a must-have in this kind of a machine? What DTMF remote functions do we need as a minimum, and are there any features that we should have that other controllers don't offer? ( We will be writing our own code for the controller, an Atmega microprocessor) Has anyone ever attempted a servo controlled duplexer? Did it work? 73, Allen VHS AF60F
Re: [Repeater-Builder] Need to pay someone to properly install repeater system in our school
Perhaps movie theaters could also be built in old Kroger stores? 73, Paul, AE4KR - Original Message - From: Butch Kanvick To: repeater-builder@yahoogroups.com Sent: Thursday, July 23, 2009 8:28 PM Subject: RE: [Repeater-Builder] Need to pay someone to properly install repeater system in our school As an educator, I agree 100%. Turned the darn phones off, administrators, educators and students. Butch, KE7FEL/r -- To: Repeater-Builder@yahoogroups.com From: ya...@carrollmechanical.net Date: Thu, 23 Jul 2009 16:52:59 -0400 Subject: Re: [Repeater-Builder] Need to pay someone to properly install repeater system in our school Perhaps a policy of turning off cell phones when people enter the school would be more appropriate. A learning environment is no place for a telephone. -John Stanley Stanukinos wrote: As far as the ATT service goes you need to get to the Engineering department so that your repeater system for their serive can be approved. What city are you in? I may be able to get a contact for you. Stan -- *From:* rddow...@swbell.net rddow...@swbell.net *To:* Repeater-Builder@yahoogroups.com *Sent:* Thursday, July 23, 2009 1:09:21 PM *Subject:* [Repeater-Builder] Need to pay someone to properly install repeater system in our school We converted an old Kroger grocery store into a charter school. The building has metal roofing and lots of steel beams, making it very difficult to get a good signal on our Nextel and AtT cell phones. So far we have installed antennas and amplifiers, to no avail. We would like to pay someone to visit the school and make everything work. Any suggestions. R. Dale Dowell, CFO Focus Learning Academy
