Re: [Repeater-Builder] GM300 Crossband Ham repeater Bi-Directional
Scott, It may be technically possible, but there will be issues: (1) The tail of the distant repeater will prevent you from breaking into a net or conversation, except at moments when the repeater is allowed to drop by other users. If the repeater encodes a CTCSS tone only when there is a valid user on the input, you can use CTCSS-decode to solve that problem. The VHF radio monitoring the repeater's output will release the UHF transmitter when the user on the input unkeys, allowing you to break in before the tail drops. (2) Transmitter duty cycle. If the repeater stays busy, you could overheat the transmitter in the UHF mobile. (3) Legal ID and control. The UHF transmitter in your vehicle will not be identifying with your callsign, which is required. If the vehicle is not close enough that you could reach it quickly, you cannot consider it to be under local control, and would need to configure it like any other repeater in this regard. I use a dual-band handheld, so I can receive the VHF repeater directly, and use the mobile only to repeat my QRP outbound UHF signal at full power/good antenna on the VHF repeater's input. I set my Alinco dual-band mobile to repeat only UHF-to-VHF, not bidirectional. That way, my periodic ID on UHF also goes out on VHF. The Alinco has extremely clean, flat audio on repeat, and nobody on the VHF repeater can tell I'm being repeated in. I never get more than a minute from my vehicle at a dead run, (comparable, I suppose, to the time it would take to run to a traditional repeater control point in your home if you were caught in the porcelain lounge,) so I consider it to be under local control. I use CTCSS on an out-of-the-way UHF link, and have never had an issue with interference or unauthorized use during a public safety event, etc. Some mobiles with crossband repeat capability (like my Alinco DR570T) require creativity in locking out bidirectional operation. Others have built-in programmable ID-ers to satisfy the need for ID on the UHF return. And many of the early ones simply built in the bidirectional function with no provision for ID, Part-97-be-damned. You'll have a world of choices rolling your own. If you could get the UHF side of the mobile repeater to be full duplex, it would be easy and slick - use a minimal repeater controller and flat-pack mobile duplexer, and just set it up like any other low-power UHF repeater with a VHF remote base. With a simplex UHF radio, you'd want to time any automatic ID to fire only when the distant repeater was being relayed, so you wouldn't be locked out of your own link receiver when it came your turn in the conversation. 73, Paul, AE4KR - Original Message - From: turboelesjuan To: Repeater-Builder@yahoogroups.com Sent: Tuesday, June 30, 2009 1:42 PM Subject: [Repeater-Builder] GM300 Crossband Ham repeater Bi-Directional A little background on what I'm trying to accomplish here; I'm a member of a Ham radio club but do not live in the city the club's repeater resides in. Due to the distance away I'm unable to access the repeater with a handheld radio without the use of a large external antenna and thats what I'd like to change. Installed in my vehicle is a Yaesu FT-8800 mobile that has ability to perform crossband repeat option. Example: A: 145.170MHz (-600khz offset) B: 438.500MHz simplex. I have a UHF Radio that I can set to 438.500MHz simplex to walk around my house and both TALK and RECEIVE traffic to and from the repeater. Basically the radio in my car has the ability to transmit and receive on BOTH frequencies. Heres my question: Is there a controller I can build which has the ability to control TWO Motorola GM300 mobiles w/16pin connectors the same way? Use each radio as a transceiver for bi-directional traffic? I already have both of the GM300 radios and they didn't cost 400$, which my 8800 Did. I want something perm. installed at my house so I can use a small UHF handheld on low power anywhere around my area to chat. Is this possible? Thanks!! -Scott
[Repeater-Builder] GM360 together with Zetron ZR320 question
Hi everybody, My name is Daniel (Romania) and I am in need for some answers regarding a Motorola GM360. I am trying to use it together with a Zetron ZR320 controller and a GM300 radio to link them together as a local repeater.I know from the service manual of the GR300 repeater (composed of 2 GM300 radios) that GM300 has some internal jumpers that need to be set up for the radio to work as a Tx or as an Rx link in the repeater. I am trying to use the GM360 as a Tx link here and the controller does not recognize it. Although the GM360 has a 20 pin accessory connector, I figured out to use the same cable (for 16 pins) but leaving external pins out (ie pins 17,18 and 19,20 on the GM360 are outside the cable connector). Like this the controller recognizes the radio as an Rx link. Please, are there any internal jumpers in the GM360 for this or any software setting might be necessary? Many thanks from now! Daniel
[possible spam] [Repeater-Builder] Re: DB-224 Phasing Harness
Well, the mysterious appendage is a tuning stub.. they put it on to help with tuning of the harness. So says the guys at Andrew. The swr looks good where the antenna is designed for, so guess I'll seal it up get on with the project. If anybody wants to know, the part number of the harness is: 083269-001 Harness Assembly Thanks, Tim W5FN --- In Repeater-Builder@yahoogroups.com, NORM KNAPP nkn...@... wrote: No, not, not really. I was going on what I had seen in a Tessco book or online... I do not remember at the moment. If I run accross this info on a brochure I would be glad to pass it along. 73 de N5NPO - Original Message - From: Repeater-Builder@yahoogroups.com Repeater-Builder@yahoogroups.com To: Repeater-Builder@yahoogroups.com Repeater-Builder@yahoogroups.com Sent: Tue Jun 30 20:14:33 2009 Subject: [possible spam] [Repeater-Builder] Re: DB-224 Phasing Harness Hi Norm, I was basing that answer on what I see in the data sheet for the DB-224 that I have. It says This series of antennas include the DB-224 (6.0db gain, circular, DB224E 9.0 db gain, off-center pattern), DB-224S (split antenna with 3.0 db and 3.0db, circular pattern) and DB-224ES (split antenna with 6.0 db and 6.0db off-center pattern) Since I don't see any references to other frequencies other than a reference to the antenna being available in 4 ranges, it's possible that db products decided to make it easier to specify a frequency band. That would make sense! You have a newer data sheet that you could attach as a .pdf? Thanks, Tim W5FN --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com , NORM KNAPP nknapp@ wrote: Actally, a DB-224E is a 138-150mhz antenna and is omni. The one you are refering to is actually a DB-224AE. It is an A band, 150-160mhz with all elements on one side for the eliptical pattern, thus the E in that case. 73 de N5NPO - Original Message - From: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Tue Jun 30 18:28:47 2009 Subject: [possible spam] [Repeater-Builder] Re: DB-224 Phasing Harness Hi Norm, The DB-224E is just a 224 that has all of the elements lined up in the same direction. Guess they had to make a separate antenna for those folks who didn't want to loosen the elements and rotate them! :-) It took about 4 months to get the harness, so not surprised they don't want to do it. They said they had to wait till they had a run of antennas to make before they'd do the harness. I honestly don't remember how much the harness was. sorry Tim --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com , NORM KNAPP nknapp@ wrote: Interesting. Is this a harness for a DB-224E? I was told a couple years ago that Andrew wouldn't sell a harness anymore. 'Bout how much was the harness? 73 de N5NPO - Original Message - From: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Tue Jun 30 17:01:29 2009 Subject: [Repeater-Builder] Re: DB-224 Phasing Harness Hi NPO, It's a replacement harness - the other one had problems, so we just ordered a new one. Haven't looked at it on analyzer - was gonna do that when I got it installed. I'll keep you posted. Tim --- In Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com , NORM KNAPP nknapp@ wrote: When you find out what is going on with that, let me know. I have installed one or two of them with that blank stub myself. Is this for a DB-224A or DB-224E or what? Is this a replacement harness? Have you swept it with a sitemaster or an antenna analyzer? 73 de N5NPO - Original Message - From: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Repeater-Builder@yahoogroups.com
[Repeater-Builder] Re: ACC RC-85 Controller Power I/O Connector Part Numbers?
Jameco has the .1 inch type connectors but they are not the 14 and 8 pin versions as used for J3 J4 on the RC-85 Repeater Controller. And there always seems to be some confusion about ordering the right type of pins for the connector. But I hopefully have all that now sorted out (regarding the right pins for the connector) and have placed an order (with Jameco). I ordered a number of different .1 inch connector bodies and just plan to cut/trim down the 10 pin size to 8 and use at least two (J3 is a 14 pin) connectors for the J3 (14 pin) connections. I'll search through Digi-key and Mouser but their Catalogs are large. Searching through large catalogs and on-line is about as fun as watching paint dry. I'd also like to ID the power connector size to source some of those plugs. cheers, s. Re: [Repeater-Builder] Re: ACC Controller Power I/O Connector Part Numbers? Skipp, please let us know what you find. I have an RC-85 that needs the connectors, too. In the meantime, I just used some individual pins and shrink tubing on each one, to go to the signal lines I needed, then off to a terminal strip on the rack panel. LJ
[Repeater-Builder] IMPORTANT - large amount of stolen equipment recovered - is some yours?
Recently the FCC busted a local jammer and when his residence was searched they found a treasure trove. There are over 200 pieces of equipment involved including laptops, desktops, over 120 handhelds and several repeaters. And broadcast equipment including a commercial grade FM transmitter. If anybody has serial numbers on file that matches anything on the lists mentioned below I think that the Ventura County Sheriff's Department would like to hear from you - contact Detective Jon Smith at (805) 494-8216 or via e-mail at jon.smith (at) ventura (dot) org The snippet below is from the CGC Communicator, a broadcast industry weekly newsletter published by Robert F. Gonsett, W6VR, cgc (at) cgc333 (dot) connectnet (dot) com, Copyright 2009, Communications General® Corporation (CGC). Reprinted with permission, and the newsletter has given permission for others to do likewise. No additional permission is needed. ** LIST OF POTENTIALLY STOLEN EQUIPMENT IN THE BONDY CASE The Ventura County Sheriff's Department has prepared its list of potentially stolen radio equipment in the Kevin Bondy case. Mr. Bondy is accused of jamming some southern California radio frequencies as discussed in recent CGC Communicator newsletters. A police search of his residence turned up an extraordinary amount of potentially stolen radio gear. Your help is needed. Is any of this equipment yours? Would you copy this story to others in the land-mobile and broadcast industries, particularly to equipment dealers and publications? If some or all of this equipment is stolen, the owners need to contact the Ventura County Sheriff pronto. Items #120 - 123 involve FM broadcast equipment; the rest is land-mobile gear (including repeaters) with a few miscellaneous items mixed in (e.g. computers, CB amateur radio gear). The first URL takes you to the list. The second URL shows pictures of the FM broadcast equipment and gives contact information for the Ventura County Sheriff. Communications General Corp. has been in touch with Broadcast Electronics concerning Item #120, the solid state 1,000 watt FM broadcast transmitter. Unfortunately, the serial number is a bit outdated for their records, but perhaps you or an equipment dealer would have a record of the sales transaction. Thanks for helping by looking over the equipment list and forwarding this story to others. Equipment list: http://earthsignals.com/add_CGC/Oaks_Mall_09-5771.pdf Photographs of the FM broadcast equipment: http://earthsignals.com/add_CGC/Letters/Stolen%20Equipment.htm Background information on Mr. Bondy: http://www.fcc.gov/eb/FieldNotices/2003/DOC-290813A1.html **
Re: [Repeater-Builder] IMPORTANT - large amount of stolen equipment recovered - is some yours?
It's all mine... unfortunately I didn't keep any of the receipts. :-) Mike, KO9I - Original Message - From: Mike Morris WA6ILQ To: Repeater-Builder@yahoogroups.com ; repea...@yahoogroups.com ; repeat...@yahoogroups.com ; l...@yahoogroups.com ; radio-p...@yahoogroups.com ; socals...@yahoogroups.com Cc: Bill Pasternak WA6ITF Sent: Wednesday, July 01, 2009 12:34 PM Subject: [Repeater-Builder] IMPORTANT - large amount of stolen equipment recovered - is some yours? Recently the FCC busted a local jammer and when his residence was searched they found a treasure trove. There are over 200 pieces of equipment involved including laptops, desktops, over 120 handhelds and several repeaters. And broadcast equipment including a commercial grade FM transmitter. If anybody has serial numbers on file that matches anything on the lists mentioned below I think that the Ventura County Sheriff's Department would like to hear from you - contact Detective Jon Smith at (805) 494-8216 or via e-mail at jon.smith (at) ventura (dot) org The snippet below is from the CGC Communicator, a broadcast industry weekly newsletter published by Robert F. Gonsett, W6VR, cgc (at) cgc333 (dot) connectnet (dot) com, Copyright 2009, Communications General® Corporation (CGC). Reprinted with permission, and the newsletter has given permission for others to do likewise. No additional permission is needed. ** LIST OF POTENTIALLY STOLEN EQUIPMENT IN THE BONDY CASE The Ventura County Sheriff's Department has prepared its list of potentially stolen radio equipment in the Kevin Bondy case. Mr. Bondy is accused of jamming some southern California radio frequencies as discussed in recent CGC Communicator newsletters. A police search of his residence turned up an extraordinary amount of potentially stolen radio gear. Your help is needed. Is any of this equipment yours? Would you copy this story to others in the land-mobile and broadcast industries, particularly to equipment dealers and publications? If some or all of this equipment is stolen, the owners need to contact the Ventura County Sheriff pronto. Items #120 - 123 involve FM broadcast equipment; the rest is land-mobile gear (including repeaters) with a few miscellaneous items mixed in (e.g. computers, CB amateur radio gear). The first URL takes you to the list. The second URL shows pictures of the FM broadcast equipment and gives contact information for the Ventura County Sheriff. Communications General Corp. has been in touch with Broadcast Electronics concerning Item #120, the solid state 1,000 watt FM broadcast transmitter. Unfortunately, the serial number is a bit outdated for their records, but perhaps you or an equipment dealer would have a record of the sales transaction. Thanks for helping by looking over the equipment list and forwarding this story to others. Equipment list: http://earthsignals.com/add_CGC/Oaks_Mall_09-5771.pdf Photographs of the FM broadcast equipment: http://earthsignals.com/add_CGC/Letters/Stolen%20Equipment.htm Background information on Mr. Bondy: http://www.fcc.gov/eb/FieldNotices/2003/DOC-290813A1.html **
[Repeater-Builder] Motorola Mototrbo Repeaters Linked
Last Saturday June 27, three Mototrbo repeaters were successfully linked via an Internet connection between California and Iowa. All three repeaters are in the 440 MHz amateur radio band and are currently linked full time. The Mototrbo repeaters, mobiles and portables are completely digital. Audio quality is very clear and natural. There are two voice time slots and in my case, one slot is connected to the other repeaters. The second voice slot is not and can be used for local repeated QSOs. Two conversations can occur at the same time. GPS and text messaging are also supported. Mobile and portable digital coverage appears to be better than my analog repeater that was removed from the same repeater antenna. If you have a Mototrbo repeater and would like to learn more about linking it to us, please contact me. Randy WB0VHB
Re: [Repeater-Builder] IMPORTANT - large amount of stolen equipment recovered - is some yours?
Not that impressive really. Whats all this crap worth, maybe $20k? Not really that much money. FM broadcast parts pop up in rather strange places these days for cheap since theres really not much legitimate commercial market for a boat-anchor transmitter. You'd think someone smart/slick enough to get away with stealing that much gear would likely be smart enough to not get busted by the FCC for screwing with mall cops. Did this guy sell LM radio/programming for a living? JS Mike Morris WA6ILQ wrote: Recently the FCC busted a local jammer and when his residence was searched they found a treasure trove. There are over 200 pieces of equipment involved including laptops, desktops, over 120 handhelds and several repeaters. And broadcast equipment including a commercial grade FM transmitter. If anybody has serial numbers on file that matches anything on the lists mentioned below I think that the Ventura County Sheriff's Department would like to hear from you - contact Detective Jon Smith at (805) 494-8216 or via e-mail at jon.smith (at) ventura (dot) org The snippet below is from the CGC Communicator, a broadcast industry weekly newsletter published by Robert F. Gonsett, W6VR, cgc (at) cgc333 (dot) connectnet (dot) com, Copyright 2009, Communications General® Corporation (CGC). Reprinted with permission, and the newsletter has given permission for others to do likewise. No additional permission is needed. ** LIST OF POTENTIALLY STOLEN EQUIPMENT IN THE BONDY CASE The Ventura County Sheriff's Department has prepared its list of potentially stolen radio equipment in the Kevin Bondy case. Mr. Bondy is accused of jamming some southern California radio frequencies as discussed in recent CGC Communicator newsletters. A police search of his residence turned up an extraordinary amount of potentially stolen radio gear. Your help is needed. Is any of this equipment yours? Would you copy this story to others in the land-mobile and broadcast industries, particularly to equipment dealers and publications? If some or all of this equipment is stolen, the owners need to contact the Ventura County Sheriff pronto. Items #120 - 123 involve FM broadcast equipment; the rest is land-mobile gear (including repeaters) with a few miscellaneous items mixed in (e.g. computers, CB amateur radio gear). The first URL takes you to the list. The second URL shows pictures of the FM broadcast equipment and gives contact information for the Ventura County Sheriff. Communications General Corp. has been in touch with Broadcast Electronics concerning Item #120, the solid state 1,000 watt FM broadcast transmitter. Unfortunately, the serial number is a bit outdated for their records, but perhaps you or an equipment dealer would have a record of the sales transaction. Thanks for helping by looking over the equipment list and forwarding this story to others. Equipment list: http://earthsignals.com/add_CGC/Oaks_Mall_09-5771.pdf http://earthsignals.com/add_CGC/Oaks_Mall_09-5771.pdf Photographs of the FM broadcast equipment: http://earthsignals.com/add_CGC/Letters/Stolen%20Equipment.htm http://earthsignals.com/add_CGC/Letters/Stolen%20Equipment.htm Background information on Mr. Bondy: http://www.fcc.gov/eb/FieldNotices/2003/DOC-290813A1.html http://www.fcc.gov/eb/FieldNotices/2003/DOC-290813A1.html **
Re: [Repeater-Builder] DB-224 patterns on side of tower.
Back when we had to submit an antenna pattern in order to get a repeater license for the ham bands, I mounted four elements of a DB-224 directly on one leg of a Rhon 25 tower and mounted the two tower sections on an antenna test pedestal and ran the pattern. With the antenna sections directly in line and pointed away from the tower, we had 9 dB gain in the favored direction, 6 dB gain at plus and minus 90 deg, and 3 dB gain off the back side of the tower. The plot was perfectly round with the 3 dB offset for the center point of the plot. 73 - Jim W5ZIT --- On Tue, 6/30/09, tahrens301 tahr...@swtexas.net wrote: From: tahrens301 tahr...@swtexas.net Subject: [Repeater-Builder] DB-224 patterns on side of tower. To: Repeater-Builder@yahoogroups.com Date: Tuesday, June 30, 2009, 2:35 PM Hi Folks, We are putting up the DB-224 on the side of the tower, which is one of those large 3 legged towers. (like you see at microwave telephone sites). I have the DB-products data sheet on the 224, and it has some plots for side mounting on the tower. The plot in question is the 224E (all in line, pointed away from the tower). According to DBprod, it would give the appropriate pattern for our desired area. However, one of the old salts here (who has final say-so) says that you really have to put some left and right angulation on the elements to get that pattern. I guess the real question is how positioning on the side of the large tower affects the pattern - if the elements are directly perpendicular to the tower leg, versus having some rotation on the leg. I'm thinking that we will probably just have to experiment with what we get per old-salt's method see how it works. Anybody have any other ideas? Thanks, Tim W5FN
Re: [Repeater-Builder] DB-224 patterns on side of tower.
I've modeled various homebrew, low-band colinears side-mounted off small towers, and been surprised to see the same thing...nearly perfectly round patterns, but with the center offset from the tower's physical location in the direction of expected gain. I've never tried modeling anything like a water tower leg, or other massive support... 73, Paul, AE4KR - Original Message - From: Jim Brown To: Repeater-Builder@yahoogroups.com Sent: Wednesday, July 01, 2009 4:46 PM Subject: Re: [Repeater-Builder] DB-224 patterns on side of tower. Back when we had to submit an antenna pattern in order to get a repeater license for the ham bands, I mounted four elements of a DB-224 directly on one leg of a Rhon 25 tower and mounted the two tower sections on an antenna test pedestal and ran the pattern. With the antenna sections directly in line and pointed away from the tower, we had 9 dB gain in the favored direction, 6 dB gain at plus and minus 90 deg, and 3 dB gain off the back side of the tower. The plot was perfectly round with the 3 dB offset for the center point of the plot. 73 - Jim W5ZIT --- On Tue, 6/30/09, tahrens301 tahr...@swtexas.net wrote: From: tahrens301 tahr...@swtexas.net Subject: [Repeater-Builder] DB-224 patterns on side of tower. To: Repeater-Builder@yahoogroups.com Date: Tuesday, June 30, 2009, 2:35 PM Hi Folks... According to DBprod, it would give the appropriate pattern for our desired area. However, one of the old salts here (who has final say-so) says that you really have to put some left and right angulation on the elements to get that pattern... .
Re: [Repeater-Builder] DB-224 patterns on side of tower.
Did you do any others? I'm guessing that this was done on the Decibel antenna range, maybe? Chuck WB2EDV - Original Message - From: Jim Brown To: Repeater-Builder@yahoogroups.com Sent: Wednesday, July 01, 2009 6:46 PM Subject: Re: [Repeater-Builder] DB-224 patterns on side of tower. Back when we had to submit an antenna pattern in order to get a repeater license for the ham bands, I mounted four elements of a DB-224 directly on one leg of a Rhon 25 tower and mounted the two tower sections on an antenna test pedestal and ran the pattern. With the antenna sections directly in line and pointed away from the tower, we had 9 dB gain in the favored direction, 6 dB gain at plus and minus 90 deg, and 3 dB gain off the back side of the tower. The plot was perfectly round with the 3 dB offset for the center point of the plot. 73 - Jim W5ZIT
Re: [Repeater-Builder] GM300 Crossband Ham repeater Bi-Directional
I will avoid going into the technical and political rant of... Why cheap mobile cross-band repeaters hooked to my properly working much more expensive real repeater are bad..., since we've hashed it out here on this list before, and just say this: Call the repeater owner of the repeater you're THINKING about doing this to, and ask their opinion of it. If they say, Please don't do it. Respect their wishes. I can definitely say that in all the time I've run repeaters, the only two things I've had to DF were jammers, and mobile cross-band repeaters built into user rigs that were set up wrong -- where the owner wasn't able to hear that they were stuck in transmit -- that I as a repeater operator had no control over -- that were parked somewhere transmitting crap into our repeaters. We generally do not welcome such operations on our systems nowadays. I can tell some people are doing it, but they seem to have their heads on straight, always run CTCSS on their input frequency, and pay attention to what the thing's doing. Had one ham years ago that would put his carrier squelch only crossbander in that mode and parked his car in a parking garage downtown (high RF environment) for two weeks straight with it transmitting crap into a high mountain repeater. A little hunting found his input frequency and it wasn't me, but I know who ran his truck battery dead... on purpose. I would have been happier if it'd blown the finals, really... after two weeks of listening to the thing and three days of actively hunting it. Think about the following: - Are you going to give a way to control your cross-bander to the control operator of the repeater you're connecting it to? - Is your crossbander going to ID and let folks know it's a cross-bander so they can come beat you with a Wouff Hong if you lock up their system? - Does your FT-8800 properly ID, or are you ID'ing it saying you're operating through a repeater? I'm actually TRYING to be nice here. The words cross-band repeater make my blood boil, since I've been on the receiving end of... Bend over, I'm hooking my crappy cross-bander to your repeater with 150 miles+ of coverage but my crappy HT and rubber duck can't hit it, and I am too lazy to do the RF math to see that I just need a better antenna at VHF... end of this far too many times... There are just better options... lots better... Think about who you'll be inconveniencing if you build a cross-band repeater, and build in a way for THEM to turn it off... over the air preferrably, but a phone line power switch would work too. That'd only be reasonable since they probably already have that feature on THEIR repeater you're linking into... if they built theirs right. Sorry about the rant... if you want REAL ideas on how to do something totally different so you can communicate with the far-away repeater... holler. Plenty of ways to do that without a cross-band junkpile... at least you were looking at relatively good rigs for doing it... compared to that broad-as-a-barn-door front end on that FT-8800! -- Nate Duehr, WY0X n...@natetech.com On Tue, 30 Jun 2009 15:42 +, turboelesjuan kd0...@gmail.com wrote: A little background on what I'm trying to accomplish here; I'm a member of a Ham radio club but do not live in the city the club's repeater resides in. Due to the distance away I'm unable to access the repeater with a handheld radio without the use of a large external antenna and thats what I'd like to change. Installed in my vehicle is a Yaesu FT-8800 mobile that has ability to perform crossband repeat option. Example: A: 145.170MHz (-600khz offset) B: 438.500MHz simplex. I have a UHF Radio that I can set to 438.500MHz simplex to walk around my house and both TALK and RECEIVE traffic to and from the repeater. Basically the radio in my car has the ability to transmit and receive on BOTH frequencies. Heres my question: Is there a controller I can build which has the ability to control TWO Motorola GM300 mobiles w/16pin connectors the same way? Use each radio as a transceiver for bi-directional traffic? I already have both of the GM300 radios and they didn't cost 400$, which my 8800 Did. I want something perm. installed at my house so I can use a small UHF handheld on low power anywhere around my area to chat. Is this possible? Thanks!! -Scott References 1. http://groups.yahoo.com/group/Repeater-Builder/message/92328;_ylc=X3oDMTM1OWZ2ajhzBF9TAzk3MzU5NzE0BGdycElkAzEwNDE2OARncnBzcElkAzE3MDUwNjMxMDgEbXNnSWQDOTIzMjgEc2VjA2Z0cgRzbGsDdnRwYwRzdGltZQMxMjQ2Mzk4NTQyBHRwY0lkAzkyMzI4 2. http://groups.yahoo.com/group/Repeater-Builder/post;_ylc=X3oDMTJwY2VwaDVoBF9TAzk3MzU5NzE0BGdycElkAzEwNDE2OARncnBzcElkAzE3MDUwNjMxMDgEbXNnSWQDOTIzMjgEc2VjA2Z0cgRzbGsDcnBseQRzdGltZQMxMjQ2Mzk4NTQy?act=replymessageNum=92328 3. http://groups.yahoo.com/group/Repeater-Builder/post;_ylc=X3oDMTJkZTBlNGc0BF9TAzk3MzU5NzE0BGdycElkAzEwNDE2OARncnBzcElkAzE3MDUwNjMxMDgEc2VjA2Z0cgRzbGsDbnRwYwRzdGltZQMxMjQ2Mzk4NTQy 4.
RE: [Repeater-Builder] DB-224 patterns on side of tower.
Back when we had to submit an antenna pattern in order to get a repeater license for the ham bands, I mounted four elements of a DB-224 directly on one leg of a Rhon 25 tower and mounted the two tower sections on an antenna test pedestal and ran the pattern. With the antenna sections directly in line and pointed away from the tower, we had 9 dB gain in the favored direction, 6 dB gain at plus and minus 90 deg, and 3 dB gain off the back side of the tower. The plot was perfectly round with the 3 dB offset for the center point of the plot. I'm not trying to pick a fight here, but this seems to defy the laws of physics. There would have to be nulls that were quite deep elsewhere in the pattern aside from the four azimuths you cited if those values were indeed valid. Think about this, a grossy simplified example that would be difficult to achive in the practical world, but valid in theory nonetheless. Say you have an omnidirectional antenna that has some gain due to elevation pattern compression (for example, a stacked dipole array like we're talking about). Or it could even be an inefficient antenna (rubber duck) that has negative gain relative to a dipole. The omni gain isn't really important, it just serves as reference, but for sake of argument say it's a 4-bay dipole array that has 6 dBd gain omni. So, 6 dBd would be 0 dBr (r=reference). Now we do something to alter the azimuth pattern which results in there being a 90 degree arc that has 9 dBd (+3 dBr) gain uniformly over that arc, two 90 degree arcs that have 6 dBd (+0 dBr) gain uniformly over those arcs, leaving a fourth 90 degree arc. What's the gain over that remaining 90 degree arc assuming it, too, is unform across its 90 degrees? If you answered 3 dBd (-3 dBr), you're wrong. If you answered 0 dB (-6 dBr), you're wrong. In fact, you'd be infinitely wrong if you answered anything other than negative infinity dB's (i.e. ZERO radiation). Using your examples/numbers above, and assuming a perfectly round pattern offset from the center by 3 dB plotted as a typical logarithmic polar plot, you're saying that over an arc of 180 degrees (the forward direction) the gain was a minimum of 6 dBd (0 dBr), and a maximum of 9 dBd (+3 dBr), correct? That would be impossible as you couldn't take enough power out of that remaining 180 degree arc on the backside to ever balance out the forward gain you claim to have achieved! There would have to be other deep nulls elsewhere in the pattern for there to ever being a chance of those gain values being being possible. If it helps to understand this better, think of a two-way power divider. A perfect two-way power divider would yield -3dB at each of its output ports relative to the input signal. Let's say the input power is 0 dBm, so at each port we have -3 dBm. Now say we modify the power divider so that one port is 3 dB hotter than what it was originally, resulting in 0 dBm coming out this hot port. What's left coming out the weak port? Hint: it's NOT -6 dBm!!! Antennas can't create power, they can only direct it where you want it to go. An antenna that has 100 watts at its input terminals can't radiate more than 100 watts total. It can concentrate more power in certain directions (i.e. gain), but the sum-total of the radiated power can't be more than the input power. --- Jeff WN3A
Re: [Repeater-Builder] DB-224 patterns on side of tower.
For what it's worth, the pattern shown in the Decibel catalog for the DB224 with all elements pointing the same direction, on a top-mounted mast, shows 9 dB to the front, 6 dB to the sides and 3 dB to the back of the mast. Almost a circle, offset. Chuck WB2EDV - Original Message - From: Jeff DePolo j...@broadsci.com To: Repeater-Builder@yahoogroups.com Sent: Wednesday, July 01, 2009 8:11 PM Subject: RE: [Repeater-Builder] DB-224 patterns on side of tower. Back when we had to submit an antenna pattern in order to get a repeater license for the ham bands, I mounted four elements of a DB-224 directly on one leg of a Rhon 25 tower and mounted the two tower sections on an antenna test pedestal and ran the pattern. With the antenna sections directly in line and pointed away from the tower, we had 9 dB gain in the favored direction, 6 dB gain at plus and minus 90 deg, and 3 dB gain off the back side of the tower. The plot was perfectly round with the 3 dB offset for the center point of the plot. I'm not trying to pick a fight here, but this seems to defy the laws of physics. There would have to be nulls that were quite deep elsewhere in the pattern aside from the four azimuths you cited if those values were indeed valid. Think about this, a grossy simplified example that would be difficult to achive in the practical world, but valid in theory nonetheless. Say you have an omnidirectional antenna that has some gain due to elevation pattern compression (for example, a stacked dipole array like we're talking about). Or it could even be an inefficient antenna (rubber duck) that has negative gain relative to a dipole. The omni gain isn't really important, it just serves as reference, but for sake of argument say it's a 4-bay dipole array that has 6 dBd gain omni. So, 6 dBd would be 0 dBr (r=reference). Now we do something to alter the azimuth pattern which results in there being a 90 degree arc that has 9 dBd (+3 dBr) gain uniformly over that arc, two 90 degree arcs that have 6 dBd (+0 dBr) gain uniformly over those arcs, leaving a fourth 90 degree arc. What's the gain over that remaining 90 degree arc assuming it, too, is unform across its 90 degrees? If you answered 3 dBd (-3 dBr), you're wrong. If you answered 0 dB (-6 dBr), you're wrong. In fact, you'd be infinitely wrong if you answered anything other than negative infinity dB's (i.e. ZERO radiation). Using your examples/numbers above, and assuming a perfectly round pattern offset from the center by 3 dB plotted as a typical logarithmic polar plot, you're saying that over an arc of 180 degrees (the forward direction) the gain was a minimum of 6 dBd (0 dBr), and a maximum of 9 dBd (+3 dBr), correct? That would be impossible as you couldn't take enough power out of that remaining 180 degree arc on the backside to ever balance out the forward gain you claim to have achieved! There would have to be other deep nulls elsewhere in the pattern for there to ever being a chance of those gain values being being possible. If it helps to understand this better, think of a two-way power divider. A perfect two-way power divider would yield -3dB at each of its output ports relative to the input signal. Let's say the input power is 0 dBm, so at each port we have -3 dBm. Now say we modify the power divider so that one port is 3 dB hotter than what it was originally, resulting in 0 dBm coming out this hot port. What's left coming out the weak port? Hint: it's NOT -6 dBm!!! Antennas can't create power, they can only direct it where you want it to go. An antenna that has 100 watts at its input terminals can't radiate more than 100 watts total. It can concentrate more power in certain directions (i.e. gain), but the sum-total of the radiated power can't be more than the input power. --- Jeff WN3A Yahoo! Groups Links
RE: [Repeater-Builder] DB-224 patterns on side of tower.
Maybe it's a fudged pattern. The Marketing Department always trumps the Engineering Department when it comes to product specs. The pattern on Andrew's web site shows 9 dBd forward gain, and only about 1 or 2 dB off the back. That's for free-space with all elements in a line. I still feel it's rather optimistic. If I had the time and energy, I'd compute the RMS power using the gain shown every 10 degrees or so and see what it comes out to, but I'm pretty confident it would be over 100%, i.e. bogus. Their sample pattern when side-mounted on a tower shows 9 dBd forward gain and -2 dBd off the back away from the tower, again with all elements in a line. That may be getting closer to being realistic. --- Jeff WN3A -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Chuck Kelsey Sent: Wednesday, July 01, 2009 8:31 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] DB-224 patterns on side of tower. For what it's worth, the pattern shown in the Decibel catalog for the DB224 with all elements pointing the same direction, on a top-mounted mast, shows 9 dB to the front, 6 dB to the sides and 3 dB to the back of the mast. Almost a circle, offset. Chuck WB2EDV - Original Message - From: Jeff DePolo j...@broadsci.com mailto:jd0%40broadsci.com To: Repeater-Builder@yahoogroups.com mailto:Repeater-Builder%40yahoogroups.com Sent: Wednesday, July 01, 2009 8:11 PM Subject: RE: [Repeater-Builder] DB-224 patterns on side of tower. Back when we had to submit an antenna pattern in order to get a repeater license for the ham bands, I mounted four elements of a DB-224 directly on one leg of a Rhon 25 tower and mounted the two tower sections on an antenna test pedestal and ran the pattern. With the antenna sections directly in line and pointed away from the tower, we had 9 dB gain in the favored direction, 6 dB gain at plus and minus 90 deg, and 3 dB gain off the back side of the tower. The plot was perfectly round with the 3 dB offset for the center point of the plot. I'm not trying to pick a fight here, but this seems to defy the laws of physics. There would have to be nulls that were quite deep elsewhere in the pattern aside from the four azimuths you cited if those values were indeed valid. Think about this, a grossy simplified example that would be difficult to achive in the practical world, but valid in theory nonetheless. Say you have an omnidirectional antenna that has some gain due to elevation pattern compression (for example, a stacked dipole array like we're talking about). Or it could even be an inefficient antenna (rubber duck) that has negative gain relative to a dipole. The omni gain isn't really important, it just serves as reference, but for sake of argument say it's a 4-bay dipole array that has 6 dBd gain omni. So, 6 dBd would be 0 dBr (r=reference). Now we do something to alter the azimuth pattern which results in there being a 90 degree arc that has 9 dBd (+3 dBr) gain uniformly over that arc, two 90 degree arcs that have 6 dBd (+0 dBr) gain uniformly over those arcs, leaving a fourth 90 degree arc. What's the gain over that remaining 90 degree arc assuming it, too, is unform across its 90 degrees? If you answered 3 dBd (-3 dBr), you're wrong. If you answered 0 dB (-6 dBr), you're wrong. In fact, you'd be infinitely wrong if you answered anything other than negative infinity dB's (i.e. ZERO radiation). Using your examples/numbers above, and assuming a perfectly round pattern offset from the center by 3 dB plotted as a typical logarithmic polar plot, you're saying that over an arc of 180 degrees (the forward direction) the gain was a minimum of 6 dBd (0 dBr), and a maximum of 9 dBd (+3 dBr), correct? That would be impossible as you couldn't take enough power out of that remaining 180 degree arc on the backside to ever balance out the forward gain you claim to have achieved! There would have to be other deep nulls elsewhere in the pattern for there to ever being a chance of those gain values being being possible. If it helps to understand this better, think of a two-way power divider. A perfect two-way power divider would yield -3dB at each of its output ports relative to the input signal. Let's say the input power is 0 dBm, so at each port we have -3 dBm. Now say we modify the power divider so that one port is 3 dB hotter than what it was originally, resulting in 0 dBm coming out this hot port. What's left coming out the weak port? Hint: it's NOT -6 dBm!!! Antennas can't create power, they can only direct it where you want it to go. An antenna that has 100 watts at its input terminals can't radiate more than 100 watts
RE: [Repeater-Builder] DB-224 patterns on side of tower.
Their sample pattern when side-mounted on a tower shows 9 dBd forward gain and -2 dBd off the back away from the tower, again with all elements in a line. That may be getting closer to being realistic. Err...upon closer look (zooming in on the PDF)...it's more like -3 to -4 dBd off the back. --- Jeff WN3A
Re: [Repeater-Builder] Motorola Mototrbo Repeaters Linked
Randy, I am not familiar Mototrbo but would like to know if the repeater is designed for and comes with the necessary hardware and software for linking via IP networks? If not what type of gateway devices were used in your project? Thank you, Bill, WA8WG - Original Message - From: wb0vhb ran...@farmtel.net To: Repeater-Builder@yahoogroups.com Sent: Wednesday, July 01, 2009 4:02 PM Subject: [Repeater-Builder] Motorola Mototrbo Repeaters Linked Last Saturday June 27, three Mototrbo repeaters were successfully linked via an Internet connection between California and Iowa. All three repeaters are in the 440 MHz amateur radio band and are currently linked full time. The Mototrbo repeaters, mobiles and portables are completely digital. Audio quality is very clear and natural. There are two voice time slots and in my case, one slot is connected to the other repeaters. The second voice slot is not and can be used for local repeated QSOs. Two conversations can occur at the same time. GPS and text messaging are also supported. Mobile and portable digital coverage appears to be better than my analog repeater that was removed from the same repeater antenna. If you have a Mototrbo repeater and would like to learn more about linking it to us, please contact me. Randy WB0VHB Yahoo! Groups Links
[Repeater-Builder] Re: DB-224 patterns on side of tower.
--- In Repeater-Builder@yahoogroups.com, Jeff DePolo j...@... wrote: Their sample pattern when side-mounted on a tower shows 9 dBd forward gain and -2 dBd off the back away from the tower, again with all elements in a line. That may be getting closer to being realistic. Several years ago I ran a real-world test using our repeater as an RF source. I could remotely switch between a top-mounted DB224 in the omni configuration, and an Antenna Specialists ASP601, which is basically the same antenna made by another manufacturer. The A/S antenna had it's dipoles directly mounted to one leg of the tower, which is about 15 in. between legs, and all in line. It was mounted 40 ft. lower on a 180 ft. tower, so it will naturally show about, I think, 2db lower field strength at many miles away because it is lower. Using the top antenna as 0db reference, I put on many miles and took numerous measurements at pretty much random locations at distances of 5-25 miles using my step attenuator. In the favored direction, the A/S showed 2-3db gain over the top antenna. At 90 degrees either side, it was down perhaps 2db. Off the back it was 9-10db down. Was it scientific? No. Was it useful and interesting? Yes. Laryn K8TVZ
Re: [Repeater-Builder] DB-224 patterns on side of tower.
We used a Scientific Atlanta turntable on top of a 5 story building with the signal source ground mounted about 500 ft away. The turntable was tilted to be at right angles to the signal source. The E-Systems range was available at the time. WR5ADU and WR5ADV were issued with that antenna pattern submitted. Many folks just drew a circle and submitted that along with the application, but we throught they were serious about an actual antenna pattern. 73 - Jim W5ZIT --- On Wed, 7/1/09, Chuck Kelsey wb2...@roadrunner.com wrote: From: Chuck Kelsey wb2...@roadrunner.com Subject: Re: [Repeater-Builder] DB-224 patterns on side of tower. To: Repeater-Builder@yahoogroups.com Date: Wednesday, July 1, 2009, 5:59 PM Did you do any others? I'm guessing that this was done on the Decibel antenna range, maybe? Chuck WB2EDV - Original Message - From: Jim Brown To: Repeater-Builder@ yahoogroups. com Sent: Wednesday, July 01, 2009 6:46 PM Subject: Re: [Repeater-Builder] DB-224 patterns on side of tower. Back when we had to submit an antenna pattern in order to get a repeater license for the ham bands, I mounted four elements of a DB-224 directly on one leg of a Rhon 25 tower and mounted the two tower sections on an antenna test pedestal and ran the pattern. With the antenna sections directly in line and pointed away from the tower, we had 9 dB gain in the favored direction, 6 dB gain at plus and minus 90 deg, and 3 dB gain off the back side of the tower. The plot was perfectly round with the 3 dB offset for the center point of the plot. 73 - Jim W5ZIT
RE: [Repeater-Builder] DB-224 patterns on side of tower.
I won't try to argue with you Jeff, but those patterns might still be on file at the FCC somewhere. This test was done on a professional antenna range by the same folks who verified all the antennas that we mounted on the airborne reconnaissance aircraft for the military. We have mounted complete fuselage sections on this test range and done both horizontal and vertical patterns. We only did the horizontal pattern for the DB-224 elements mounted directly to the Rhon 25 sections. The gain figures I quoted are dBd reference the dipole mounted in place of the DB-224 before the test. The Scientific Atlanta turntable was connected to a circular strip chart and the amplitude measurements were recorded directly to the strip chart which was submitted. The turntable was mounted on top of a five story building with the signal source about 500 feet away mounted near the ground. The tilt angle between the source and antenna to be measured is to prevent ground reflections from entering into the results. I did not attempt to do any measurements to make sure it was a circle, but it sure looked like a circle to me - with the 3 dB offset from the center toward the direction the dipoles were pointed. Again, the results were perfectly smooth with a 9 dB gain in the direction the dipoles were pointed, varying very smoothly with no nulls or dips to 3 dB gain in the direction through the tower oposite the dipoles. I don't see your point on where the energy comes from to make the extra 3 dB gain, as it obviously comes from the 3 dB reduction in gain on the back side of the tower compared to an omni antenna. 73 - Jim W5ZIT --- On Wed, 7/1/09, Jeff DePolo j...@broadsci.com wrote: From: Jeff DePolo j...@broadsci.com Subject: RE: [Repeater-Builder] DB-224 patterns on side of tower. To: Repeater-Builder@yahoogroups.com Date: Wednesday, July 1, 2009, 7:11 PM Back when we had to submit an antenna pattern in order to get a repeater license for the ham bands, I mounted four elements of a DB-224 directly on one leg of a Rhon 25 tower and mounted the two tower sections on an antenna test pedestal and ran the pattern. With the antenna sections directly in line and pointed away from the tower, we had 9 dB gain in the favored direction, 6 dB gain at plus and minus 90 deg, and 3 dB gain off the back side of the tower. The plot was perfectly round with the 3 dB offset for the center point of the plot. I'm not trying to pick a fight here, but this seems to defy the laws of physics. There would have to be nulls that were quite deep elsewhere in the pattern aside from the four azimuths you cited if those values were indeed valid. Think about this, a grossy simplified example that would be difficult to achive in the practical world, but valid in theory nonetheless. Say you have an omnidirectional antenna that has some gain due to elevation pattern compression (for example, a stacked dipole array like we're talking about). Or it could even be an inefficient antenna (rubber duck) that has negative gain relative to a dipole. The omni gain isn't really important, it just serves as reference, but for sake of argument say it's a 4-bay dipole array that has 6 dBd gain omni. So, 6 dBd would be 0 dBr (r=reference) . Now we do something to alter the azimuth pattern which results in there being a 90 degree arc that has 9 dBd (+3 dBr) gain uniformly over that arc, two 90 degree arcs that have 6 dBd (+0 dBr) gain uniformly over those arcs, leaving a fourth 90 degree arc. What's the gain over that remaining 90 degree arc assuming it, too, is unform across its 90 degrees? If you answered 3 dBd (-3 dBr), you're wrong. If you answered 0 dB (-6 dBr), you're wrong. In fact, you'd be infinitely wrong if you answered anything other than negative infinity dB's (i.e. ZERO radiation). Using your examples/numbers above, and assuming a perfectly round pattern offset from the center by 3 dB plotted as a typical logarithmic polar plot, you're saying that over an arc of 180 degrees (the forward direction) the gain was a minimum of 6 dBd (0 dBr), and a maximum of 9 dBd (+3 dBr), correct? That would be impossible as you couldn't take enough power out of that remaining 180 degree arc on the backside to ever balance out the forward gain you claim to have achieved! There would have to be other deep nulls elsewhere in the pattern for there to ever being a chance of those gain values being being possible. If it helps to understand this better, think of a two-way power divider. A perfect two-way power divider would yield -3dB at each of its output ports relative to the input signal. Let's say the input power is 0 dBm, so at each port we have -3 dBm. Now say we modify the power divider so that one port is 3 dB hotter than what it was originally, resulting in 0 dBm coming out this hot port. What's left
[Repeater-Builder] Comprod 2 bay UHF Dipole
OK Brains, I really am interested in the Comprod 2 bay UHF dipole with half wave spacing. I am told with the elements point east the antenna will achieve 5.5db gain to the north and souht. The tower will be behind the antenna to the west so don't care about any gain or loss that direction. Does what I wrote above make sense? My understanding with quarter wave spacing the pattern will change but mine will be half wave spacing. Oh yes, the antenna will be about 30-36 inchs off the leg of the 160ft Rohn self supporting tower up at about 140ft in the air. I am interested in any responses. 73 and tnx, Brian, k5in
