RE: [Repeater-Builder] Motorola cabinet key wanted
Thank You , I now have a Shortcut on My Desktop to that and Even on My USB Thunbdrive and 3 1/4 floppy disk , Yes some still use them and that has nothing to do with old age lol Happy Repeater Building Don KA9QJG This is what you saw - and this is what you are looking for: http://www.repeater-builder.com/keyspage/keyspage-index.html Bill Hudson W6CBS Ex-Motorola 1983 Let Me tell You youngsters out here How bad Memory loss is , as Some of us get older I could swear that on this group or one I use Someone Posted a File about KEYS But for the life of Me I cannot find it , It listed Everything . And I have searched for 2 hours trying to help but did not find it. Oh well just wait Some of you will catch up soon , My favorite saying is that it's Great as We get Older to learn something New every day it is remembering it is the problem PS Please tell Me that I am not just making this up Happy Repeater Building Don KA9QJG
[Repeater-Builder] Re: Motorola Power Supply Questiona
Hey Gareth, Nice to hear from you. Thanks for the info on the power supply and I will heed your warnings about battery types. I am possibly able to get a circuit diagram for this from another group member and this will be very helpful in my possible future use of this supply. My primary want for this is for its DC supply at 25 odd amps for powering 12v devices in the mobile home, so if it pans out it is not that suitable for charging my Gels ... I can live with that. Might be the push I need to get some solar panels bought and installed :-) Thanks again. Graham. --- In Repeater-Builder@yahoogroups.com, Gareth Bennett gare...@... wrote: Hi Graham, We recently threw out dozens of similar items from Transpower sites that were in service as constant voltage float chargers in substations. What you may have is a constant voltage charger with supervision circuitry by the looks of it, and a way to set voltage and overcurrent foldback. These chargers are great for conventional lead acid batteries, but generally do not have temperature compensation for sealed construction cells such as SLA / AGM etc. Most importantly is to go by the battery manufacturers specificationsMore often than not, the charger is the cheapest item in the installation. Regards, Gareth - Original Message - From: zl3tda To: Repeater-Builder@yahoogroups.com Sent: Monday, February 22, 2010 11:20 PM Subject: [Repeater-Builder] Motorola Power Supply Questiona Hello all from down under! I have a Motorola power supply that has come out of a repeater installation and I am looking for some info on it. What I am mostly wanting to know is what a small row of header type pins are for - external meters etc perhaps? The numbers on the transformer are - 25D84880N02 / TB602 / Scumacher Elect 93-013-418. I did a google and got a few hits ... all NON English :-) I want to use this to provide the DC power needs in my mobile home while I am connected to grid power (got a few hungry devices - Ham radios,audio and Rf amps and LCD TV's). I see there is a charging circuit as well and would hope this would be suitable to keep my deep cycle batteries topped up - no solar panels installed at this time. I am wondering if the charging circuit is able to look after my batteries and has 1-2-3 stage charging - bulk, absorption and float ... or would it just be float? Having prematurely lost a couple of very big deep cycle batteries due to perhaps over zealous charging from the built-in charger on the old Trace inverter I have been using, I am keen to look after my new set as best I can. Is the charger in this type of supply up to the task or would I be best to use a smaller good quality three stage charger separate. Oh ... and to keep it on topic - I have a couple of Tait T800 repeaters in a rack in the bus for events and festival comms. Here is a link to what it looks like http://tinyurl.com/yg9p9oy Any help much appreciated. Thanks! Graham Shaw ZL3TV Mid Canterbury New Zealand
Re: [Repeater-Builder] Re: Motorola Power Supply Questiona
Hiya Graham, One of the reasons we binned these type of supplies was for excessive AC ripple that they produced, just be mindful of this on your adventures with sealed type batteries. By the way, If you need solar panels try this crowd out over in Oz, http://www.rockby.com.au/searchres.cfm?select=102offset=31stock_no=37970 Quite often they have some unbeatable specials if you are on their mailing list. Cheers for now Gareth - Original Message - From: zl3tda To: Repeater-Builder@yahoogroups.com Sent: Wednesday, February 24, 2010 9:47 PM Subject: [Repeater-Builder] Re: Motorola Power Supply Questiona Hey Gareth, Nice to hear from you. Thanks for the info on the power supply and I will heed your warnings about battery types. I am possibly able to get a circuit diagram for this from another group member and this will be very helpful in my possible future use of this supply. My primary want for this is for its DC supply at 25 odd amps for powering 12v devices in the mobile home, so if it pans out it is not that suitable for charging my Gels ... I can live with that. Might be the push I need to get some solar panels bought and installed :-) Thanks again. Graham. --- In Repeater-Builder@yahoogroups.com, Gareth Bennett gare...@... wrote: Hi Graham, We recently threw out dozens of similar items from Transpower sites that were in service as constant voltage float chargers in substations. What you may have is a constant voltage charger with supervision circuitry by the looks of it, and a way to set voltage and overcurrent foldback. These chargers are great for conventional lead acid batteries, but generally do not have temperature compensation for sealed construction cells such as SLA / AGM etc. Most importantly is to go by the battery manufacturers specificationsMore often than not, the charger is the cheapest item in the installation. Regards, Gareth - Original Message - From: zl3tda To: Repeater-Builder@yahoogroups.com Sent: Monday, February 22, 2010 11:20 PM Subject: [Repeater-Builder] Motorola Power Supply Questiona Hello all from down under! I have a Motorola power supply that has come out of a repeater installation and I am looking for some info on it. What I am mostly wanting to know is what a small row of header type pins are for - external meters etc perhaps? The numbers on the transformer are - 25D84880N02 / TB602 / Scumacher Elect 93-013-418. I did a google and got a few hits ... all NON English :-) I want to use this to provide the DC power needs in my mobile home while I am connected to grid power (got a few hungry devices - Ham radios,audio and Rf amps and LCD TV's). I see there is a charging circuit as well and would hope this would be suitable to keep my deep cycle batteries topped up - no solar panels installed at this time. I am wondering if the charging circuit is able to look after my batteries and has 1-2-3 stage charging - bulk, absorption and float ... or would it just be float? Having prematurely lost a couple of very big deep cycle batteries due to perhaps over zealous charging from the built-in charger on the old Trace inverter I have been using, I am keen to look after my new set as best I can. Is the charger in this type of supply up to the task or would I be best to use a smaller good quality three stage charger separate. Oh ... and to keep it on topic - I have a couple of Tait T800 repeaters in a rack in the bus for events and festival comms. Here is a link to what it looks like http://tinyurl.com/yg9p9oy Any help much appreciated. Thanks! Graham Shaw ZL3TV Mid Canterbury New Zealand
Re: [Repeater-Builder] Re: Motorola Power Supply Questiona
The photo looks like a repeater supply. Many repeater supplies provided a 9.6v DC low current output for the receiver and exciter, some had a second low current output at 13.5-13.8vDC at 3-4 amps for the other audio stages, and most had an unregulated (as high as 16v) high current output for the transmitter RF amplifier section. The 16vDC is not suitable for high current loads that expect 12-14 volts. You will cook / boil your batteries. The 25-series number is for the power transformer only. Motorola parts department always formatted their part numbers with a 2-digit prefix to identify the type of part. See http://www.repeater-builder.com/motorola/numerical-parts-categories.html TB602 is a label for a connector that goes to somewhere else in the radio cabinet. It probably has the 9.6 or 12v low current, or ? Some supplies had a battery charger circuit in them. Some had a battery backup section (i.e. an automatic load switchover from the mains supply to the battery bank. Please look for a rubber stamped number somewhere on the chassis that starts with TPN, followed by 4 digits and maybe a suffix with some letters and numbers after it - something like TPN1095A, or TPN1152B1, or something in that format. USUALLY, but not always, there is a letter after the 4 digits, occasionally there is a number after the letter, and rarely there is a number at the end. There is no way to tell exactly what voltages, or features your supply has in it without seeing the actual physical supply, or looking at the manual. If you provide the complete TPN number we can look it up to see what type of station (radio) it came from, then look at the manual for that station. BTW the TPN comes from: T = Two way radio product P = Power supply, or power supply related N = Not frequency sensitive . The last letter usually was structured like this: A Under 25 MHz B 25-54 MHz C 66-88MHz D 144-174 MHz E 390-550 MHz F 890-960 MHz N Not frequency dependent See http://www.repeater-builder.com/motorola/aaa-numbering-scheme.html Mike Morris WA6ILQ
[Repeater-Builder] Re: Motorola cabinet key wanted
Try Repeater-Builder key page http://www.repeater-builder.com/keyspage/keyspage-index.html
Re: [Repeater-Builder] Motorola cabinet key wanted
Ray, ONE FOR STARTERS, could also use one EFJohnson cabinet lock assembly as well. Thanks de Lee , K4LJP 73 On Wed, Feb 24, 2010 at 12:47 AM, ray kalbfeld rpkalbf...@hotmail.comwrote: how many Johnson keys you need? Raymond P. Kalbfeld 16850 Collins Avenue Suite 112-463 Sunny Isles Beach, Florida 33160 Cell 786-267-7555 Office 305-831-1488 rpkalbf...@hotmail.com -- To: Repeater-Builder@yahoogroups.com From: localjunkpedd...@gmail.com Date: Tue, 23 Feb 2010 21:26:12 -0500 Subject: Re: [Repeater-Builder] Motorola cabinet key wanted Andy, Any possibility that you could come up with an EFJohnson Deskmate station key?? de Lee K4LJP 73 On Tue, Feb 23, 2010 at 9:18 PM, Andrew Seybold aseyb...@andrewseybold.com wrote: The Motorola key should be a 2135 and the GE Key is probably a BF10A, they are hard to find but around—I can make you copies if you want to pay the key making price and postage. Andy W6AMS *From:* Repeater-Builder@yahoogroups.com [mailto: repeater-buil...@yahoogroups.com] *On Behalf Of *Gary Schafer *Sent:* Tuesday, February 23, 2010 6:16 PM *To:* Repeater-Builder@yahoogroups.com *Subject:* [Repeater-Builder] Motorola cabinet key wanted I am in need of a cabinet key for an old Motorola base station cabinet. It is an old low band 1/4 kw rig. Had 100TH tubes in final. This is the 6 foot tall cabinet. Anyone know the key number for these? Have a key? Also have an old GE progress line base cabinet that needs a key. This cabinet is about 3 feet tall and longer than wide. Thanks! Gary K4FMX -- Always drink upstream from the herd. -- Your E-mail and More On-the-Go. Get Windows Live Hotmail Free. Sign up now. http://clk.atdmt.com/GBL/go/196390709/direct/01/ -- Always drink upstream from the herd.
[Repeater-Builder] Re: Motorola cabinet key
If it is the double sided key then its a 2553. If the cabinet has an external handle that the lock is in its a CH751. For some reason Motherola used a different key on the 6' cabinets than on the shorter (Compa) cabinets. Unfortunately I don't have a spare, but they are made by Chicago Lock Co. and they should be able to sell you what you need. Dan N8DJP
Re: [Repeater-Builder] Motorola cabinet key wanted
Hello Don, Look at the bright side of life. Tomorrow you'll be having fun looking for it again! 73, Joe, K1ike Also heading for the other side of the hill... ka9qjg wrote: Let Me tell You youngsters out here How bad Memory loss is , as Some of us get older I could swear that on this group or one I use Someone Posted a File about KEYS But for the life of Me I cannot find it , It listed Everything .
[Repeater-Builder] Ground Plane radial length for DB-201
From a Decibel Products engineer regarding the length of the radials on the DB-201: these values were determined empherically for best performance and may be due to the offset characteristics of the folded dipole. Chuck WB2EDV - Original Message - From: skipp025 skipp...@yahoo.com To: Repeater-Builder@yahoogroups.com Sent: Wednesday, February 24, 2010 1:06 AM Subject: [Repeater-Builder] Re: Ground plane yada yada allan crites wa9...@... wrote: I appreciate the contribution of the information found in the ARRL April 1962 QST article, which I have reviewed, and the technical parameters of impedance matching provided, however the information presented relates to the shortening of a 1/2 WL simple dipole from the resonant freq. terminal impedance of 72+j0 to achieve a terminal Z = 50-jXC and the subsequent removal of the XC component with a shunt XL Hairpin matching device. The gnd plane antenna in the original discussion has a 1/4 WL vertical radiating element terminal impedance of 36+j0. Any reduction of the length will result in a lower R component as well as to introduce shunt XC. If the 1/4 radiator was reduced in length proportionally as the 1/2 WL antenna was, it would have a terminal impedance of 50 divided by 72 or 0.694 times 36, resulting in a R component of about 25 Ohms. This is obviously is going the wrong way to achieve a suitable match for a 50 Ohm system. There is no way no how that the 36 Ohm 1/4 WL vertical radiator in a gnd plane antenna can be made to match 50 Ohms by the addition of a shunt XL component. Construction of the impedance on a Smith Chart verifies this. Only a series transmission line with a shunt reactance can get a impedance match to a 50 Ohm system. I would be happy to submit a Smith Chart with the appropriate series transmission line and location of the shunt stub illustrated.Â
[Repeater-Builder] Re: Ground plane yada yada
Actually, the information presented in the QST article was in reference to the practical feeding of the driven element of yagi type antennae where the normal feedpoint impedance can be quite low and may well be in the range of 8 to 15 ohms. So raising the impedance from 36 to 50 ohms with this method, that is, with a beta or hairpin match, is trivial. (Actually a 'half-beta I suppose.) A natural extension of this, and a technique perhaps more familiar, is the gamma match where the feed line is attached via a parallel conductor to the driven element a distance away from the grounded center of the element and corresponding to a point on the element near 50 ohms. Then the inductive reactance of the parallel conductor is tuned out by inserting a series capacitor with the feed or shortening the driven side of the driven element. The fact that many hams, commercial manufacturers, and my personal experience, have used these methods successfully for more than half a century provides me with enough empirical evidence that the techniques are valid. 73, Al, K9SI Re: Ground plane yada yada Posted by: allan crites wa9...@arrl.net wa9zzu Date: Tue Feb 23, 2010 4:29 pm ((PST)) I appreciate the contribution of the information found in the ARRL April 1962 QST article, which I have reviewed, and the technical parameters of impedance matching provided, however the information presented relates to the shortening of a 1/2 WL simple dipole from the resonant freq. terminal impedance of 72+j0 to achieve a terminal Z = 50-jXC and the subsequent removal of the XC component with a shunt XL Hairpin matching device. The gnd plane antenna in the original discussion has a 1/4 WL vertical radiating element terminal impedance of 36+j0. Any reduction of the length will result in a lower R component as well as to introduce shunt XC. If the 1/4 radiator was reduced in length proportionally as the 1/2 WL antenna was, it would have a terminal impedance of 50 divided by 72 or 0.694 times 36, resulting in a R component of about 25 Ohms. This is obviously is going the wrong way to achieve a suitable match for a 50 Ohm system. There is no way no how that the 36 Ohm 1/4 WL vertical radiator in a gnd plane antenna can be made to match 50 Ohms by the addition of a shunt XL component. Construction of the impedance on a Smith Chart verifies this. Only a series transmission line with a shunt reactance can get a impedance match to a 50 Ohm system. I would be happy to submit a Smith Chart with the appropriate series transmission line and location of the shunt stub illustrated. a. snip Al Wolfe k...@... wrote: The straight skinny about the beta or hairpin match can be found in a QST article, April 1962, by Gooch and Gardiner. It explains how this matching scheme works. The driven element is shortened making it capacitive. Then the inductive reactance of the hairpin or beta section re-resonates the element by canceling the capacitive reactance of the shortened element while raising the feedpoint impedance at the same time. Theory, formulae, and practical examples are all in the article. The inverse is also desribed in the article where the element is lengthened to make it inductive and a series capacitor used to re-resonate the antenna. Both of these methods have been used for years to manipulate the feedpoint impedence of an antenna. The beta does have the advantage of presenting a DC ground. Al, K9SI
[Repeater-Builder] Anyone work on a Radio Specialty Mfg Mountain Top Repeater before?
I have not one but two of these gems sitting in my office right now... 2 channel crystal controlled repeaters in a nice battleship grey cabinet. I believe BLM used these here in the western states for quite a long while before switching to Daniels. A factory test sheet in one of the 3 service manuals I have specifies .15 uV sensitivity at 12 dB quieting; .21 UV sensitivity at 20 dB quieting with a whopping 8 ma draw in standby, swinging to 1.8 amps in repeat. Overall looking at the design, it appears quite logically laid out. Looks like power output is around 8 watts and factory spec was 145 to 174 MHz in 1983. We're looking at rerocking it for 147 MHz as a portable repeater in a Pelican case with a Q2220 duplexer... ICM has already quoted $21 a rock with a 2 week lead time. Any one have a chance to work on one of these before?
[Repeater-Builder] Genesis series UHF antennas
A while back didn't someone post that they had UHF Motorola Genesis series antennas available at a good price? I am looking for a few, maybe as many as a dozen, if the price is right. Thanks, Albert
Re: [Repeater-Builder] Anyone work on a Radio Specialty Mfg Mountain Top Repeater before?
Just the standard words of wisdom; be sure you verify that it works, and how it works before starting any conversion. That way you only have to deal with one problem at a time not compounded problems. Milt N3LTQ - Original Message - From: AJ To: Repeater-Builder@yahoogroups.com Sent: Wednesday, February 24, 2010 10:39 AM Subject: [Repeater-Builder] Anyone work on a Radio Specialty Mfg Mountain Top Repeater before? I have not one but two of these gems sitting in my office right now... 2 channel crystal controlled repeaters in a nice battleship grey cabinet. I believe BLM used these here in the western states for quite a long while before switching to Daniels. A factory test sheet in one of the 3 service manuals I have specifies .15 uV sensitivity at 12 dB quieting; .21 UV sensitivity at 20 dB quieting with a whopping 8 ma draw in standby, swinging to 1.8 amps in repeat. Overall looking at the design, it appears quite logically laid out. Looks like power output is around 8 watts and factory spec was 145 to 174 MHz in 1983. We're looking at rerocking it for 147 MHz as a portable repeater in a Pelican case with a Q2220 duplexer... ICM has already quoted $21 a rock with a 2 week lead time. Any one have a chance to work on one of these before?
Re: [Repeater-Builder] Anyone work on a Radio Specialty Mfg Mountain Top Repeater before?
Completely understood :) The first unit I was able to verify is acting correctly on the 173/171 pair in to a dummy load with 8 watts out, broke squelch at .11 uV. Second unit was missing the TX crystal; swapped between cabinets and had identical results. On Wed, Feb 24, 2010 at 9:24 AM, Milt men...@pa.net wrote: Just the standard words of wisdom; be sure you verify that it works, and how it works before starting any conversion. That way you only have to deal with one problem at a time not compounded problems. Milt N3LTQ - Original Message - *From:* AJ aj.grant...@gmail.com *To:* Repeater-Builder@yahoogroups.com *Sent:* Wednesday, February 24, 2010 10:39 AM *Subject:* [Repeater-Builder] Anyone work on a Radio Specialty Mfg Mountain Top Repeater before? I have not one but two of these gems sitting in my office right now... 2 channel crystal controlled repeaters in a nice battleship grey cabinet. I believe BLM used these here in the western states for quite a long while before switching to Daniels. A factory test sheet in one of the 3 service manuals I have specifies .15 uV sensitivity at 12 dB quieting; .21 UV sensitivity at 20 dB quieting with a whopping 8 ma draw in standby, swinging to 1.8 amps in repeat. Overall looking at the design, it appears quite logically laid out. Looks like power output is around 8 watts and factory spec was 145 to 174 MHz in 1983. We're looking at rerocking it for 147 MHz as a portable repeater in a Pelican case with a Q2220 duplexer... ICM has already quoted $21 a rock with a 2 week lead time. Any one have a chance to work on one of these before?
[Repeater-Builder] dual band convertacom
I know I am going to get the singular answer of WHY but I really would like some technical input on this. In my car I have an old Genesis series convertacom connected to a dual band Comet antenna. I often will swap my VHF and UHF HT back and forth and utilize the dual band capability of my antenna. It works pretty well. What I would like to get some input on however, is how to run some power with this setup. Of course the easiest would be to get a amateur dual band amplifier, but I already have a VHF and a UHF (N1275A and N1274A) amplifier. What I would like to do is parallel these two amps with some kind of switching/duplexer setup so that I could easily switch from VHF to UHF. My initial idea was to run an antenna switch from the convertacom to the amps so I can manually select which one the signal goes to. Then on the output side of the amps I thought about using an antenna duplexer on the output of the amps to feed the antenna. I was also thinking of running a switch to alternately select which amp was receiving DC power, but I don't know if that would be necessary. (Could I leave both amps powered on in this situation?) So, does this sound about right or am I going off the deep end? Thanks Albert
Re: [Repeater-Builder] dual band convertacom
Not why but WHY !! On Wed, Feb 24, 2010 at 11:56 AM, hitekgearhead hitekgearh...@hotmail.comwrote: I know I am going to get the singular answer of WHY but I really would like some technical input on this. In my car I have an old Genesis series convertacom connected to a dual band Comet antenna. I often will swap my VHF and UHF HT back and forth and utilize the dual band capability of my antenna. It works pretty well. What I would like to get some input on however, is how to run some power with this setup. Of course the easiest would be to get a amateur dual band amplifier, but I already have a VHF and a UHF (N1275A and N1274A) amplifier. What I would like to do is parallel these two amps with some kind of switching/duplexer setup so that I could easily switch from VHF to UHF. My initial idea was to run an antenna switch from the convertacom to the amps so I can manually select which one the signal goes to. Then on the output side of the amps I thought about using an antenna duplexer on the output of the amps to feed the antenna. I was also thinking of running a switch to alternately select which amp was receiving DC power, but I don't know if that would be necessary. (Could I leave both amps powered on in this situation?) So, does this sound about right or am I going off the deep end? Thanks Albert -- Always drink upstream from the herd.
Re: [Repeater-Builder] dual band convertacom
2 coaxial switches will work, and you could leave power on. Given that I know what I am capable of and this type of system would lead to muliple failures by me as I failed to remember to switch things. If it was me I would just move the coax connectors as I swapped radios. I have done something like this in the past and got irritated and tossed the whole thing is favor of a wide band type of amp, which also has its issues of tuning and retuning --- On Wed, 2/24/10, Lee Pennington localjunkpedd...@gmail.com wrote: From: Lee Pennington localjunkpedd...@gmail.com Subject: Re: [Repeater-Builder] dual band convertacom To: Repeater-Builder@yahoogroups.com Date: Wednesday, February 24, 2010, 9:07 AM Not why but WHY !! On Wed, Feb 24, 2010 at 11:56 AM, hitekgearhead hitekgearh...@hotmail.com wrote: I know I am going to get the singular answer of WHY but I really would like some technical input on this. In my car I have an old Genesis series convertacom connected to a dual band Comet antenna. I often will swap my VHF and UHF HT back and forth and utilize the dual band capability of my antenna. It works pretty well. What I would like to get some input on however, is how to run some power with this setup. Of course the easiest would be to get a amateur dual band amplifier, but I already have a VHF and a UHF (N1275A and N1274A) amplifier. What I would like to do is parallel these two amps with some kind of switching/duplexer setup so that I could easily switch from VHF to UHF. My initial idea was to run an antenna switch from the convertacom to the amps so I can manually select which one the signal goes to. Then on the output side of the amps I thought about using an antenna duplexer on the output of the amps to feed the antenna. I was also thinking of running a switch to alternately select which amp was receiving DC power, but I don't know if that would be necessary. (Could I leave both amps powered on in this situation?) So, does this sound about right or am I going off the deep end? Thanks Albert -- Always drink upstream from the herd.
RE: [Repeater-Builder] dual band convertacom
My initial idea was to run an antenna switch from the convertacom to the amps so I can manually select which one the signal goes to. Then on the output side of the amps I thought about using an antenna duplexer on the output of the amps to feed the antenna. I think you'll find that using a second duplexer (cross-band coupler) on the input to the amps will be cheaper than buying a high-quality coaxial relay to switch between the two. Then you don't have to switch anything. I was also thinking of running a switch to alternately select which amp was receiving DC power, but I don't know if that would be necessary. As long as the switch or cross-band coupler affords sufficient isolation to keep the wrong amplifier from switching into transmit mode, it shouldn't matter, unless you're concerned about battery drain. --- Jeff
Re: [Repeater-Builder] dual band convertacom
Try using a dual amp. And dual antenna then you won't forget to switch. Just my 2 cents Ki4ljm Marc Lonstein M.O. Unlimited Inc. P.O. Box 5364 Fort Lauderdale, FL 33310-5364 Ph: 954-720-9200 Ph: 561-368-3557 Fax: 561-368-1885 mailto:m...@mounlimited.com www.mounlimited.com This e-mail transmission contains information intended only for the use of the recipient(s) named above. Further, it contains information that may be privileged and confidential. If you are not the intended recipient, you are hereby notified that any dissemination, distribution, or copying of this message (including any attachments) is strictly prohibited. If you have received this e-mail in error, please notify the sender by reply e-mail and then delete this message from your e-mail system. Thank you for your compliance. -Original Message- From: Chris Quirk w6...@yahoo.com Date: Wed, 24 Feb 2010 09:17:00 To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] dual band convertacom 2 coaxial switches will work, and you could leave power on. Given that I know what I am capable of and this type of system would lead to muliple failures by me as I failed to remember to switch things. If it was me I would just move the coax connectors as I swapped radios. I have done something like this in the past and got irritated and tossed the whole thing is favor of a wide band type of amp, which also has its issues of tuning and retuning --- On Wed, 2/24/10, Lee Pennington localjunkpedd...@gmail.com wrote: From: Lee Pennington localjunkpedd...@gmail.com Subject: Re: [Repeater-Builder] dual band convertacom To: Repeater-Builder@yahoogroups.com Date: Wednesday, February 24, 2010, 9:07 AM Not why but WHY !! On Wed, Feb 24, 2010 at 11:56 AM, hitekgearhead hitekgearh...@hotmail.com wrote: I know I am going to get the singular answer of WHY but I really would like some technical input on this. In my car I have an old Genesis series convertacom connected to a dual band Comet antenna. I often will swap my VHF and UHF HT back and forth and utilize the dual band capability of my antenna. It works pretty well. What I would like to get some input on however, is how to run some power with this setup. Of course the easiest would be to get a amateur dual band amplifier, but I already have a VHF and a UHF (N1275A and N1274A) amplifier. What I would like to do is parallel these two amps with some kind of switching/duplexer setup so that I could easily switch from VHF to UHF. My initial idea was to run an antenna switch from the convertacom to the amps so I can manually select which one the signal goes to. Then on the output side of the amps I thought about using an antenna duplexer on the output of the amps to feed the antenna. I was also thinking of running a switch to alternately select which amp was receiving DC power, but I don't know if that would be necessary. (Could I leave both amps powered on in this situation?) So, does this sound about right or am I going off the deep end? Thanks Albert -- Always drink upstream from the herd.
Re: [Repeater-Builder] Re: Ground plane yada yada
In the gnd plane example the feed point is in series with the driven element, and in the example in which you are referring there is a tap up the driven element understandably to get to a higher impedance and the feed is in parallel to the driven element (as in a tap up an inductor in a resonant circuit) with with a series inductor, resonated with the series capacitor. There's a difference. One is series fed and the other is parallel fed. There is no doubt that the method you espouse is valid, but your comparison to a series fed element is not. One could also run a short section of coax in parallel with but spaced away from the driven element with the center conductor of the coax connecting to the tap on the element, and achieve a wider operating bandwidth. The coax feed can be shown on a Smith Chart to be the equivalent to the series LC for impedance matching purposes. WA9ZZU --- On Wed, 2/24/10, Al Wolfe k...@arrl.net wrote: From: Al Wolfe k...@arrl.net Subject: [Repeater-Builder] Re: Ground plane yada yada To: Repeater-Builder@yahoogroups.com Date: Wednesday, February 24, 2010, 9:27 AM Actually, the information presented in the QST article was in reference to the practical feeding of the driven element of yagi type antennae where the normal feedpoint impedance can be quite low and may well be in the range of 8 to 15 ohms. So raising the impedance from 36 to 50 ohms with this method, that is, with a beta or hairpin match, is trivial. (Actually a 'half-beta I suppose.) A natural extension of this, and a technique perhaps more familiar, is the gamma match where the feed line is attached via a parallel conductor to the driven element a distance away from the grounded center of the element and corresponding to a point on the element near 50 ohms. Then the inductive reactance of the parallel conductor is tuned out by inserting a series capacitor with the feed or shortening the driven side of the driven element. The fact that many hams, commercial manufacturers, and my personal experience, have used these methods successfully for more than half a century provides me with enough empirical evidence that the techniques are valid. 73, Al, K9SI Re: Ground plane yada yada Posted by: allan crites wa9...@arrl. net wa9zzu Date: Tue Feb 23, 2010 4:29 pm ((PST)) I appreciate the contribution of the information found in the ARRL April 1962 QST article, which I have reviewed, and the technical parameters of impedance matching provided, however the information presented relates to the shortening of a 1/2 WL simple dipole from the resonant freq. terminal impedance of 72+j0 to achieve a terminal Z = 50-jXC and the subsequent removal of the XC component with a shunt XL Hairpin matching device. The gnd plane antenna in the original discussion has a 1/4 WL vertical radiating element terminal impedance of 36+j0. Any reduction of the length will result in a lower R component as well as to introduce shunt XC. If the 1/4 radiator was reduced in length proportionally as the 1/2 WL antenna was, it would have a terminal impedance of 50 divided by 72 or 0.694 times 36, resulting in a R component of about 25 Ohms. This is obviously is going the wrong way to achieve a suitable match for a 50 Ohm system. There is no way no how that the 36 Ohm 1/4 WL vertical radiator in a gnd plane antenna can be made to match 50 Ohms by the addition of a shunt XL component. Construction of the impedance on a Smith Chart verifies this. Only a series transmission line with a shunt reactance can get a impedance match to a 50 Ohm system. I would be happy to submit a Smith Chart with the appropriate series transmission line and location of the shunt stub illustrated. a. snip Al Wolfe k...@... wrote: The straight skinny about the beta or hairpin match can be found in a QST article, April 1962, by Gooch and Gardiner. It explains how this matching scheme works. The driven element is shortened making it capacitive. Then the inductive reactance of the hairpin or beta section re-resonates the element by canceling the capacitive reactance of the shortened element while raising the feedpoint impedance at the same time. Theory, formulae, and practical examples are all in the article. The inverse is also desribed in the article where the element is lengthened to make it inductive and a series capacitor used to re-resonate the antenna. Both of these methods have been used for years to manipulate the feedpoint impedence of an antenna. The beta does have the advantage of presenting a DC ground. Al, K9SI
Re: [Repeater-Builder] dual band convertacom
On Wed, 24 Feb 2010, hitekgearhead wrote: What I would like to do is parallel these two amps with some kind of switching/duplexer setup so that I could easily switch from VHF to UHF. My initial idea was to run an antenna switch from the convertacom to the amps so I can manually select which one the signal goes to. Then on the output side of the amps I thought about using an antenna duplexer on the output of the amps to feed the antenna. I was also thinking of running a switch to alternately select which amp was receiving DC power, but I don't know if that would be necessary. (Could I leave both amps powered on in this situation?) So, does this sound about right or am I going off the deep end? Buy two duplexers (diplexers) from some ham source, put one between the MTVA and the amps, and the other between the amps and the antenna. No switching needed. If one really wanted to get wonky, you'd put another MTVA in the car and use a linear dual-band HT amp, but you'd have to look at the third-order intercept points on a spectrum analyzer to make sure the amplifier doesn't create mixing products, and alter the drive level of the two HTs to make sure the amp doesn't go non-linear when trying to amplify 145MHz and 440MHz at the same time. -- Kris Kirby, KE4AHR Disinformation Analyst
[Repeater-Builder] TLE1714A PA Mod to 440 MHz?
Hello, I have a TLE1714A PA (470-512 MHz) That I would like to use for my Repeater on 449 MHz. I see in the manual there is a few capacitor, transistor and inductor changes compared to the TLE1713A PA (450-470 MHz ) PA. I also noted the microstrip is a different part number and can see there are changes in the stripline compared to the TLE1714A. Has anyone successfully modified the TLE1714A to operate on the upper end of the 440 band? Thanks, Louie KA2PFL
Re: [Repeater-Builder] Re: Can the 4th harmonic of 1250 AM keep UHF repeaters locked up?
On 2/23/2010 3:11 PM, Jim WB5OXQ inb Waco, TX wrote: Is it possible the AM signal is getting into an audio stage instead of the receiver front end? I had that happen once. Same here. All audio inteconnects are now tiny coax cables at that site now, installed with shield grounded at ONE end... Nate WY0X Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/Repeater-Builder/join (Yahoo! ID required) * To change settings via email: repeater-builder-dig...@yahoogroups.com repeater-builder-fullfeatu...@yahoogroups.com * To unsubscribe from this group, send an email to: repeater-builder-unsubscr...@yahoogroups.com * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
RE: [Repeater-Builder] Re: Can the 4th harmonic of 1250 AM keep UHF repeaters locked up?
On 2/23/2010 3:11 PM, Jim WB5OXQ inb Waco, TX wrote: Is it possible the AM signal is getting into an audio stage instead of the receiver front end? I had that happen once. Same here. All audio inteconnects are now tiny coax cables at that site now, installed with shield grounded at ONE end... Nate WY0X At AM broadcast sites or studios co-located with the transmitter, hard-grounding the shield at one end and RF-coupling the shield at the other end to the equipment ground via caps (0.01 uF as a rule of thumb) is often the most effective technique in many situations. --- Jeff WN3A
RE: [Repeater-Builder] Motorola cabinet key wanted
Ok, thanks to all that replied. It looks like it is a 2553 that I need. Looking at the chart it looks like the CH751 is for the old outdoor cabinet and the 2553 is for the indoor cabinet. Also looks like the GE cabinet that I have is probably the desk mate and takes the LL201 key. Ted, K9MDM sent me an email saying that he has those keys for sale. I will probably get them from him. Thanks again to all Gary K4FMX _ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Bill Hudson Sent: Wednesday, February 24, 2010 1:51 AM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Motorola cabinet key wanted This is what you saw - and this is what you are looking for: http://www.repeater-builder.com/keyspage/keyspage-index.html Bill Hudson W6CBS Ex-Motorola 1983 _ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of ka9qjg Sent: Tuesday, February 23, 2010 10:35 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Motorola cabinet key wanted Let Me tell You youngsters out here How bad Memory loss is , as Some of us get older I could swear that on this group or one I use Someone Posted a File about KEYS But for the life of Me I cannot find it , It listed Everything . And I have searched for 2 hours trying to help but did not find it. Oh well just wait Some of you will catch up soon , My favorite saying is that it's Great as We get Older to learn something New every day it is remembering it is the problem PS Please tell Me that I am not just making this up Happy Repeater Building Don KA9QJG
Re: [Repeater-Builder] Re: Can the 4th harmonic of 1250 AM keep UHF repeaters locked up?
If it was just audio then there would be no feedback of the PL/DPL tones, keeping the repeater locked up. Good advice though. Jeff DePolo wrote: On 2/23/2010 3:11 PM, Jim WB5OXQ inb Waco, TX wrote: Is it possible the AM signal is getting into an audio stage instead of the receiver front end? I had that happen once. Same here. All audio inteconnects are now tiny coax cables at that site now, installed with shield grounded at ONE end... Nate WY0X At AM broadcast sites or studios co-located with the transmitter, hard-grounding the shield at one end and RF-coupling the shield at the other end to the equipment ground via caps (0.01 uF as a rule of thumb) is often the most effective technique in many situations. --- Jeff WN3A Yahoo! Groups Links * To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ * Your email settings: Individual Email | Traditional * To change settings online go to: http://groups.yahoo.com/group/Repeater-Builder/join (Yahoo! ID required) * To change settings via email: repeater-builder-dig...@yahoogroups.com repeater-builder-fullfeatu...@yahoogroups.com * To unsubscribe from this group, send an email to: repeater-builder-unsubscr...@yahoogroups.com * Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
Re: [Repeater-Builder] dual band convertacom
On the comment below all I can mention is from my experience which may or may not be valid in this case. When running amplifiers through diplexors as suggested I have damaged the out put transistors on both units, no I am not sure exactly what did it but as both amplifiers failed my guess is as one came up to full power and the other went non linear something happened and the diplexor failed to isolate as desired and expected. If anyone can sort out what happened let me know --- On Wed, 2/24/10, Kris Kirby k...@catonic.us wrote: From: Kris Kirby k...@catonic.us Subject: Re: [Repeater-Builder] dual band convertacom To: Repeater-Builder@yahoogroups.com Date: Wednesday, February 24, 2010, 11:01 AM On Wed, 24 Feb 2010, hitekgearhead wrote: What I would like to do is parallel these two amps with some kind of switching/duplexer setup so that I could easily switch from VHF to UHF. My initial idea was to run an antenna switch from the convertacom to the amps so I can manually select which one the signal goes to. Then on the output side of the amps I thought about using an antenna duplexer on the output of the amps to feed the antenna. I was also thinking of running a switch to alternately select which amp was receiving DC power, but I don't know if that would be necessary. (Could I leave both amps powered on in this situation?) So, does this sound about right or am I going off the deep end? Buy two duplexers (diplexers) from some ham source, put one between the MTVA and the amps, and the other between the amps and the antenna. No switching needed. If one really wanted to get wonky, you'd put another MTVA in the car and use a linear dual-band HT amp, but you'd have to look at the third-order intercept points on a spectrum analyzer to make sure the amplifier doesn't create mixing products, and alter the drive level of the two HTs to make sure the amp doesn't go non-linear when trying to amplify 145MHz and 440MHz at the same time. -- Kris Kirby, KE4AHR Disinformation Analyst Yahoo! Groups Links
RE: [Repeater-Builder] Motorola cabinet key wanted
OK - you are getting closer. Yes, from your original description of the Motorola cabinet, the 2553 is correct. It is the Micor / Motrac era. Yes, the CH751 is the large beige upright cabinet with a handle on it. Motrac era. NO, if it is truly a GE DESKMATE cabinet, it will take a BF10a key. While the documentation I referred you to discusses LL201 for a deskmate cabinet, I have never seen an LL201 work on a deskmate cabinet. The deskmate was during the progress line era. LL201, is for what was known as pre progress line. Just for fun, I tried an LL201 in a GE DESKMATE cabinet, and it would not work. I'm sure there is an exception somewhere in the world. I have just about every key for all radios including EF Johnson. I hate getting locked out of radios and cabinets. Ha ha Bill Hudson W6CBS _ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Gary Schafer Sent: Wednesday, February 24, 2010 1:16 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Motorola cabinet key wanted Ok, thanks to all that replied. It looks like it is a 2553 that I need. Looking at the chart it looks like the CH751 is for the old outdoor cabinet and the 2553 is for the indoor cabinet. Also looks like the GE cabinet that I have is probably the desk mate and takes the LL201 key. Ted, K9MDM sent me an email saying that he has those keys for sale. I will probably get them from him. Thanks again to all Gary K4FMX _ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Bill Hudson Sent: Wednesday, February 24, 2010 1:51 AM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Motorola cabinet key wanted This is what you saw - and this is what you are looking for: http://www.repeater http://www.repeater-builder.com/keyspage/keyspage-index.html -builder.com/keyspage/keyspage-index.html Bill Hudson W6CBS Ex-Motorola 1983 _ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of ka9qjg Sent: Tuesday, February 23, 2010 10:35 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Motorola cabinet key wanted Let Me tell You youngsters out here How bad Memory loss is , as Some of us get older I could swear that on this group or one I use Someone Posted a File about KEYS But for the life of Me I cannot find it , It listed Everything . And I have searched for 2 hours trying to help but did not find it. Oh well just wait Some of you will catch up soon , My favorite saying is that it's Great as We get Older to learn something New every day it is remembering it is the problem PS Please tell Me that I am not just making this up Happy Repeater Building Don KA9QJG
RE: [Repeater-Builder] Motorola cabinet key wanted
Hi Bill, Well now I am having second thoughts! The Motorola cabinets that I have are older than the Motrac era. I can't recall the model of the radios but the finals in one are 100TH tubes. That was before the motrac. The cabinets are at my farm in Wisconsin so I can't run out and look at them for a few months. They are not the black wrinkle paint finish. They have 3 or 4 simpson meters on the top outside. On the GE cabinet I am not sure what vintage that is. The key list that you referred to shows the LL201 being for some GE desk mates and also the BF10A for later ones I assume. Thanks! Gary K4FMX _ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Bill Hudson Sent: Wednesday, February 24, 2010 5:30 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Motorola cabinet key wanted OK - you are getting closer. Yes, from your original description of the Motorola cabinet, the 2553 is correct. It is the Micor / Motrac era. Yes, the CH751 is the large beige upright cabinet with a handle on it. Motrac era. NO, if it is truly a GE DESKMATE cabinet, it will take a BF10a key. While the documentation I referred you to discusses LL201 for a deskmate cabinet, I have never seen an LL201 work on a deskmate cabinet. The deskmate was during the progress line era. LL201, is for what was known as pre progress line. Just for fun, I tried an LL201 in a GE DESKMATE cabinet, and it would not work. I'm sure there is an exception somewhere in the world. I have just about every key for all radios including EF Johnson. I hate getting locked out of radios and cabinets. Ha ha Bill Hudson W6CBS _ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Gary Schafer Sent: Wednesday, February 24, 2010 1:16 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Motorola cabinet key wanted Ok, thanks to all that replied. It looks like it is a 2553 that I need. Looking at the chart it looks like the CH751 is for the old outdoor cabinet and the 2553 is for the indoor cabinet. Also looks like the GE cabinet that I have is probably the desk mate and takes the LL201 key. Ted, K9MDM sent me an email saying that he has those keys for sale. I will probably get them from him. Thanks again to all Gary K4FMX _ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Bill Hudson Sent: Wednesday, February 24, 2010 1:51 AM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Motorola cabinet key wanted This is what you saw - and this is what you are looking for: http://www.repeater http://www.repeater-builder.com/keyspage/keyspage-index.html -builder.com/keyspage/keyspage-index.html Bill Hudson W6CBS Ex-Motorola 1983 _ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of ka9qjg Sent: Tuesday, February 23, 2010 10:35 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Motorola cabinet key wanted Let Me tell You youngsters out here How bad Memory loss is , as Some of us get older I could swear that on this group or one I use Someone Posted a File about KEYS But for the life of Me I cannot find it , It listed Everything . And I have searched for 2 hours trying to help but did not find it. Oh well just wait Some of you will catch up soon , My favorite saying is that it's Great as We get Older to learn something New every day it is remembering it is the problem PS Please tell Me that I am not just making this up Happy Repeater Building Don KA9QJG
RE: [Repeater-Builder] Re: Can the 4th harmonic of 1250 AM keep UHF repeaters locked up?
Don't be too sure about that. Once the am station signal gets into the receiver it can go anywhere and cause havoc. It could be getting into the IF or the mixer once picked up by cables. 73 Gary K4FMX -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:Repeater- buil...@yahoogroups.com] On Behalf Of KT9AC Sent: Wednesday, February 24, 2010 4:42 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Re: Can the 4th harmonic of 1250 AM keep UHF repeaters locked up? If it was just audio then there would be no feedback of the PL/DPL tones, keeping the repeater locked up. Good advice though. Jeff DePolo wrote: On 2/23/2010 3:11 PM, Jim WB5OXQ inb Waco, TX wrote: Is it possible the AM signal is getting into an audio stage instead of the receiver front end? I had that happen once. Same here. All audio inteconnects are now tiny coax cables at that site now, installed with shield grounded at ONE end... Nate WY0X At AM broadcast sites or studios co-located with the transmitter, hard-grounding the shield at one end and RF-coupling the shield at the other end to the equipment ground via caps (0.01 uF as a rule of thumb) is often the most effective technique in many situations. --- Jeff WN3A Yahoo! Groups Links
RE: [Repeater-Builder] Motorola cabinet key wanted
gary let me know which keys you think you'll need i 'm certain i have a wide selection. mot-ge-efj-rca-and other even older. mdm Ted Bleiman K9MDM MDM Radio If its in stock...we've got it! P O Box 31353 - Chicago ,IL 60631-0353 Phone 773. 255. 9838 fax 773.775.8096 see our offerings on www.twowayshopper.com www.secondhandradio.com --- On Wed, 2/24/10, Gary Schafer gascha...@comcast.net wrote: From: Gary Schafer gascha...@comcast.net Subject: RE: [Repeater-Builder] Motorola cabinet key wanted To: Repeater-Builder@yahoogroups.com Date: Wednesday, February 24, 2010, 3:15 PM Ok, thanks to all that replied. It looks like it is a 2553 that I need. Looking at the chart it looks like the CH751 is for the old outdoor cabinet and the 2553 is for the indoor cabinet. Also looks like the GE cabinet that I have is probably the “desk mate” and takes the LL201 key. Ted, K9MDM sent me an email saying that he has those keys for sale. I will probably get them from him. Thanks again to all Gary K4FMX From: Repeater-Builder@ yahoogroups. com [mailto: Repeater-Builder@ yahoogroups. com ] On Behalf Of Bill Hudson Sent: Wednesday, February 24, 2010 1:51 AM To: Repeater-Builder@ yahoogroups. com Subject: RE: [Repeater-Builder] Motorola cabinet key wanted This is what you saw – and this is what you are looking for: http://www.repeater -builder. com/keyspage/ keyspage- index.html Bill Hudson W6CBS Ex-Motorola 1983 From: Repeater-Builder@ yahoogroups. com [mailto: Repeater-Builder@ yahoogroups. com ] On Behalf Of ka9qjg Sent: Tuesday, February 23, 2010 10:35 PM To: Repeater-Builder@ yahoogroups. com Subject: RE: [Repeater-Builder] Motorola cabinet key wanted Let Me tell You youngsters out here How bad Memory loss is , as Some of us get older I could swear that on this group or one I use Someone Posted a File about KEYS But for the life of Me I cannot find it , It listed Everything . And I have searched for 2 hours trying to help but did not find it. Oh well just wait Some of you will catch up soon , My favorite saying is that it’s Great as We get Older to learn something New every day it is remembering it is the problem PS Please tell Me that I “am not just making this up Happy Repeater Building Don KA9QJG
RE: [Repeater-Builder] dual band convertacom
Albert, I had a very similar installation as you describe in my car, and I used a dual-band brick PA with my setup. 5W VHF yielded 50W / 4W UHF yielded 40W. My biggest issue with the setup was they side contacts on my radios wouldn't make good contact all the time with the MVA, so I yanked it in favor of a dual-band mobile. But I still have the MVA and the PA, just in case... ;-) Seeing you prefer to use separate PAs, you might want to consider two diplexers - one ahead of each PA to split the feedlines and then one behind them to re-combine them. But to be honest, IMHO this is kinda the Rube Goldberg way of doing it, I think. Compare prices - by the time you get the diplexers and other stuff, you may well be approaching the cost of one dual-band PA. Mark - N9WYS -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of hitekgearhead I know I am going to get the singular answer of WHY but I really would like some technical input on this. In my car I have an old Genesis series convertacom connected to a dual band Comet antenna. I often will swap my VHF and UHF HT back and forth and utilize the dual band capability of my antenna. It works pretty well. What I would like to get some input on however, is how to run some power with this setup. Of course the easiest would be to get a amateur dual band amplifier, but I already have a VHF and a UHF (N1275A and N1274A) amplifier. What I would like to do is parallel these two amps with some kind of switching/duplexer setup so that I could easily switch from VHF to UHF. My initial idea was to run an antenna switch from the convertacom to the amps so I can manually select which one the signal goes to. Then on the output side of the amps I thought about using an antenna duplexer on the output of the amps to feed the antenna. I was also thinking of running a switch to alternately select which amp was receiving DC power, but I don't know if that would be necessary. (Could I leave both amps powered on in this situation?) So, does this sound about right or am I going off the deep end? Thanks Albert
[Repeater-Builder] Re: Key Collection
Ted Bleiman K9MDM - MDM Radio k9...@... wrote: Gary let me know which keys you think you'll need i 'm certain i have a wide selection. mot-ge-efj-rca-and other even older. mdm Oh yeah..? Got an Allen B. Dumont, (Fred) Link key in that collection? :-) s.
Re: [Repeater-Builder] Re: Can the 4th harmonic of 1250 AM keep UHF repeaters locked up?
At 2/23/2010 17:16, you wrote: Mark et al, Yes, this repeater is using the Motorola T1500 series bandpass cavities (two each for rx and tx). I've tried running rx and tx both duplex and seperate (borrowing a nearby antenna with permission). I can hear the interference underneath my signal when I'm about 2 miles away and monitoring my signal. When its strong enough, the PL encode of the repeater keeps it locked up until the modulation from the AM station overtakes the PL being looped (voice peak). Then the repeater drops since I have a tone panel in between and not continuous PL outbound. I have tried changing the receive frequency about 75Khz lower and the interference is not present (so a 4.925Mhz split), so that serves to prove to me that this indeed a mix. I can try adding an attenuator the next time I'm out at the site. The antenna is about 300 feet up and fed with 7/8 heliax, to a Polyphaser and then superflex to the duplexer. I've also tried without the Poly, but have the same result. I have some nice Mini-Circuit pads that should work in the receive side after the duplexer, but think the receiver is simply overloaded. The cause of your interference problem is not RX overload. It is as others have suggested: a mix occurring somewhere in the near field of the antenna. Pads may eventually mask the real source of the problem, once you've added enough to drop the signal below your RX's noise floor, but you'll end up with a deaf repeater. How far away were the separate TX RX antennas when you tried that? I'd think if they were far enough apart that you would lose the mix. OTOH if a tower joint is the source of the mix (likely since a lot of length is required to couple in the AM BC station), it might be all over the tower. A similar problem was partially cured here by spraying some conductive paint into all the tower joints. Each time it was done the interference would disappear for a few months, then return. Bob NO6B
Re: [Repeater-Builder] Re: Key Collection
skipp025 wrote: Oh yeah..? Got an Allen B. Dumont, (Fred) Link key in that collection? My father had a Link FM transmitter on VHF - used a pair of 2E26's in the final. It was paired with a receiver, but I don't recall what it was. The receiver would get so hot it would burn up the tube sockets. Both were in a small Link cabinet, but the door wasn't lockable, as I remember. We did have a small/unstable DuMont oscilloscope - it sure wasn't a Tektronix. Kevin
RE: [Repeater-Builder] Re: Key Collection
Did Fred use locks? Perhaps that was your point. I don't remember locks on the mobiles or upright base stations that I had. Seems like the mobile covers went on and off similar to the GE twin coffins (which I don't remember requiring a key). It's hard to remember the details of those radios except for the 7 volt tubes. Harry, W0BL -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of skipp025 Sent: Wednesday, February 24, 2010 6:42 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Re: Key Collection Oh yeah..? Got an Allen B. Dumont, (Fred) Link key in that collection?
[Repeater-Builder] Re: motorola repeater cable problem
Old topic, but I thought I would start here rather than a new thread. I am also having difficulties in that when I plug my repeater cable between my two SM50s, the transmit radio immediately goes into transmit. I am fairly certain I have everything programmed properly, with Pin 8 programmed for DPL/PL CS Detect and Active Low. I am using this cable from Ebay http://cgi.ebay.com/Delay-Repeater-Interface-for-Motorola-GM300-Radio-NEW_W0QQitemZ150095175361QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item22f25e9ec1 and I'm wondering if it's not correct? This outfit also sells a duplex cable, but I thought that only allowed the repeater to work in both directions, not necessarily achieve what you talk about below. I'm not trying to operate crossband - just a simple GMRS repeater. Thanks for any possible advice! Phil - AD6NH/WQKP927 --- In Repeater-Builder@yahoogroups.com, Milt men...@... wrote: Dan, From your message I am guessing that you are trying to set up a crossband repeater from VHF to UHF. Otherwise you will need to explain 2 mobiles and a simplex repeater. The rear 16 pin connectors have some pins that are fixed in function (mic audio, PTT, Gnd) and some that are assigned via software (type of audio output, indication of valid PL/DPL/carrier detection). The switching functions must be configured to be active atthe proper level (High or Low). Both radios will need to be properly configured. The configuration of the cable must be bi-directional; it must pass the COS, PTT, and audio signals in both directions, GND is comman between both units. Without the proper equipment and software to program the radios and documentation of the radio and the cable it's going to be rather hard to get things properly set up. Milt N3LTQ - Original Message - From: dan d dwd71...@... To: Repeater-Builder@yahoogroups.com Sent: Tuesday, January 06, 2009 9:30 AM Subject: [Repeater-Builder] motorola repeater cable problem I have two Motorola sm50 mobiles using a repeater cable that goes between the two at the option plug in the back. I have tried every configuration two get this to work with no results. Before I condem the cable I got off ebay does anyone know of any mods or settings that need to be done to get this simplex repeater up and running. I have confirmed the radio operation itself and they are good to go. Yahoo! Groups Links
RE: [Repeater-Builder] Re: Key Collection
Yep - I even have the round grilled speaker that said Link in the felt. Bill _ From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Radioman Sent: Wednesday, February 24, 2010 4:40 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: Key Collection Did Fred use locks? Perhaps that was your point. I don't remember locks on the mobiles or upright base stations that I had. Seems like the mobile covers went on and off similar to the GE twin coffins (which I don't remember requiring a key). It's hard to remember the details of those radios except for the 7 volt tubes. Harry, W0BL -Original Message- From: Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com [mailto:Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com] On Behalf Of skipp025 Sent: Wednesday, February 24, 2010 6:42 PM To: Repeater-Builder@ mailto:Repeater-Builder%40yahoogroups.com yahoogroups.com Subject: [Repeater-Builder] Re: Key Collection Oh yeah..? Got an Allen B. Dumont, (Fred) Link key in that collection?
[Repeater-Builder] Re: New to 900mhz,, PL or DPL?
Here in southern New England where the 900MHz band has flourished in the absence of a 70cm network. I have not been personally involved in putting any of the repeaters on the air, but I can tell you that the split is pretty even between Pl/DPL. Not sure how it will work with a 800 to 900MHz conversion most of the gear used around here in intended for 900MHz use (mostly Motorola equipment). Best advice I can give you is www.gemoto.com they are the driving force behind our 33cm movement and have lots of technical knowledge. 73, Jeremy KB1REQ --- In Repeater-Builder@yahoogroups.com, kq7dx kq...@... wrote: Hello to the group, I have had a couple of really nice hams try to explain this to me but I am not getting it. Which is better. Most importantly which is better in a metropolitan city with lots of RFI and noise on the bands. Particularly 900mhz. I have seen mostly PL and just a few DPL listings so I am not sure that it is RFI motivated for the selection. So which is best for a repeater application. The receiver for the repeater will be a 800mhz Maxtrac converted to 902mhz. Thank you for your help, and if this was covered on another post please let me know. I am on a dial up and it is hard to research. 73s scott
RE: [Repeater-Builder] Re: Key Collection
What's the key number or other stamping? Now I'm going to have to look thru my key collection and find it. Somewhere I have a picture of me sitting next to my Link six meter base station, but the radio and all the spare transmitters and receivers and the mobiles are long gone. Harry, W0BL From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Bill Hudson Sent: Wednesday, February 24, 2010 8:12 PM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Re: Key Collection Yep - I even have the round grilled speaker that said Link in the felt.
RE: [Repeater-Builder] Micor UHF Repeater Base 9.6 vdc current requirement?
During receive only, the draw is about 0.125 amperes. During duplex transmit, the current draw goes up to about 0.355 amperes. These numbers were measured on one Micor station, and I would expect the current draw to vary perhaps +/- 50 mA between various stations. YMMV. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of skipp025 Sent: Tuesday, February 23, 2010 10:26 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] Micor UHF Repeater Base 9.6 vdc current requirement? re: Micor UHF Repeater Base 9.6 vdc current requirement? Any of you Micor People know the actual total 9.6 volt supply current requirement? ... as in removing the power supply and running the equipment off battery power. The 9.6 vdc is still required but at how much current? Anyone know the real measured current value? thanks in advance for your reply cheers, skipp
Re: [Repeater-Builder] Re: Key Collection
If you have a similar key, you may be able to get into the cabinet my smoking a key.. Go to Youtube to learn how, if you don't know or have forgotten. From: Radioman radio...@steamboatnews.com To: Repeater-Builder@yahoogroups.com Sent: Wed, February 24, 2010 6:39:39 PM Subject: RE: [Repeater-Builder] Re: Key Collection Did Fred use locks? Perhaps that was your point. I don't remember locks on the mobiles or upright base stations that I had. Seems like the mobile covers went on and off similar to the GE twin coffins (which I don't remember requiring a key). It's hard to remember the details of those radios except for the 7 volt tubes. Harry, W0BL -Original Message- From: Repeater-Builder@ yahoogroups. com [mailto:Repeater-Builder@ yahoogroups. com] On Behalf Of skipp025 Sent: Wednesday, February 24, 2010 6:42 PM To: Repeater-Builder@ yahoogroups. com Subject: [Repeater-Builder] Re: Key Collection Oh yeah..? Got an Allen B. Dumont, (Fred) Link key in that collection?
RE: [Repeater-Builder] New to 900mhz,, PL or DPL?
Scott, A proper answer must address the differences in the way Amateur and commercial radios encode and decode the PL (CTCSS) and DPL (CDCSS) tones. Generally, commercial-quality portable and mobile radios can encode or decode both schemes well. Again generally, most Amateur-grade radios can handle PL fairly well but not DPL. The issue here is the inability of most Amateur-grade radios to encode and decode the reverse-burst squelch-tail elimination (STE) signals. It is one of life's great pleasures to have a radio mute silently at the end of an incoming transmission, without so much as a tick instead of a crash. However, in one of life's inexplicable ironies, there are Hams who walk among us who delight in hearing squelch crashes, and can't seem to survive without them- must be fans of the old Highway Patrol TV series. The CTCSS reverse-burst STE uses a phase shift of either 180 degrees or 120 degrees (both are officially-recognized formats) to activate the muting circuits of the receiver, but the CDCSS scheme uses a brief burst of 134.4 Hz tone to accomplish the same effect. And therein is the problem with DPL- the same mute tone is used with ALL digital codes, so a co-channel user with DPL (or a CTCSS user with a nearby tone like 131.8 Hz) can mute your receiver inadvertently. Some of the cheaper Amateur-grade radios- Puxing and Alinco come to mind- use less-sophisticated methods to generate tones, and these tones sometimes are distorted enough to cause intermittent operation of CTCSS or CDCSS decoders. Perhaps crude methods would be more accurate. A 3-step approximation of a sine wave (the cheap and easy method) is a good example of crude, and is raspy. But, I digress. If the radios and stations you plan to use are capable of handling PL and DPL, go for it. I suspect that PL operation will be able to operate well with a greater number of portable and mobile radios. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of kq7dx Sent: Wednesday, February 24, 2010 12:43 PM To: Repeater-Builder@yahoogroups.com Subject: [Repeater-Builder] New to 900mhz,, PL or DPL? Hello to the group, I have had a couple of really nice hams try to explain this to me but I am not getting it. Which is better. Most importantly which is better in a metropolitan city with lots of RFI and noise on the bands. Particularly 900mhz. I have seen mostly PL and just a few DPL listings so I am not sure that it is RFI motivated for the selection. So which is best for a repeater application. The receiver for the repeater will be a 800mhz Maxtrac converted to 902mhz. Thank you for your help, and if this was covered on another post please let me know. I am on a dial up and it is hard to research. 73s scott
[Repeater-Builder] Re: Can the 4th harmonic of 1250 AM keep UHF repeaters locked up?
I agree with Bob. Mixing could also occur down at the guy anchor area, where cables are woven through the turnbuckles. Had it happen here... Laryn K8TVZ The cause of your interference problem is not RX overload. It is as others have suggested: a mix occurring somewhere in the near field of the antenna. Pads may eventually mask the real source of the problem, once you've added enough to drop the signal below your RX's noise floor, but you'll end up with a deaf repeater. How far away were the separate TX RX antennas when you tried that? I'd think if they were far enough apart that you would lose the mix. OTOH if a tower joint is the source of the mix (likely since a lot of length is required to couple in the AM BC station), it might be all over the tower. A similar problem was partially cured here by spraying some conductive paint into all the tower joints. Each time it was done the interference would disappear for a few months, then return. Bob NO6B
[Repeater-Builder] Re: Key Collection
My father had a Link FM transmitter on VHF - used a pair of 2E26's in the final Never saw that transmitter. The ones that I had used a 2E26 to drive an 829B final for VHF high. Only put out about 30 to 40 watts but it was an easy mod. to a 5894. It would smoke then; easily put out 80 to 90 watts and plates always stayed gray. I believe that transmitter was a model 1905 and the companion receiver was a 2240. Would remove the vibrator power supplies from those receivers and build an AC power supply for it, put volume and squelch controls and a speaker in the cabinet and sell them as monitor receivers before the days of scanners. None of the Link mobiles had key locks, the two-box radios used those captive 1/4 turn fasteners on the covers and the later one piece 6000 series used spring loaded latches on the sides of the drawer. The small upright cabinet (similar to a compa-station cabinet did use key locks on the doors as did the 6-foot uprights but a different handle on the bigger cabinet. They all had 2 meters and those big pilot lights with the 4 watt 117 volt bulbs in them. Then there was the 2975 series UHF mobile and base station. It was rated at 15 watts but would rarely put out over about 10 watts. Used a 5894 Tripler (!!!) driving another 5894 final. Never could figure out how they got enough drive out of a double-ended driver on an odd harmonic to drive the final; probably the main reason it rarely made rated power. Sure wish I'd kept some of those old antiques, if just for the memories. Tom DGN --- In Repeater-Builder@yahoogroups.com, Kevin Custer kug...@... wrote: skipp025 wrote: Oh yeah..? Got an Allen B. Dumont, (Fred) Link key in that collection? My father had a Link FM transmitter on VHF - used a pair of 2E26's in the final. It was paired with a receiver, but I don't recall what it was. The receiver would get so hot it would burn up the tube sockets. Both were in a small Link cabinet, but the door wasn't lockable, as I remember. We did have a small/unstable DuMont oscilloscope - it sure wasn't a Tektronix. Kevin
[Repeater-Builder] Re: Key Collection
Oh yeah..? Got an Allen B. Dumont... Back in the day I bought a bunch of those old DuMont radios at a government auction. Didn't know anything about them but I figured, how bad could they be? Well,I found out. I ordered one set of crystals, messed with the thing for a while and finally the whole mess went in the trash. About the only thing I ever encountered that was worse was a bunch of GE Accent Line UHF mobiles. It was no mystery why experienced techs. used to call them Accident Line. Anybody remember the KAAR mobiles? I don't think they even made a base station. It really wasn't too bad of a radio but, if I remember correctly, the transmitter was pretty low power, something like 5 to 7 watts. Had a bunch of those on an RCC that I serviced. They were fairly trouble-free. Tom DGN --- In Repeater-Builder@yahoogroups.com, skipp025 skipp...@... wrote: Ted Bleiman K9MDM - MDM Radio k9mdm@ wrote: Gary let me know which keys you think you'll need i 'm certain i have a wide selection. mot-ge-efj-rca-and other even older. mdm Oh yeah..? Got an Allen B. Dumont, (Fred) Link key in that collection? :-) s.
[Repeater-Builder] Re: TLE1714A PA Mod to 440 MHz?
Just put it on the air and run with it. I have been using a TLE1714A PA on 445MHz for over 15 years, and it actually puts out a little more than some of the 1713's I have used. I never did any down-banding mods to it, as it has played well as is. Efficiency is no worse than the 1713s at 440MHz. As with any Micor PA, put a few fans on it, and it will last forever. Eric K2WD --- In Repeater-Builder@yahoogroups.com, Lou ka2...@... wrote: Hello, I have a TLE1714A PA (470-512 MHz) That I would like to use for my Repeater on 449 MHz. I see in the manual there is a few capacitor, transistor and inductor changes compared to the TLE1713A PA (450-470 MHz ) PA. I also noted the microstrip is a different part number and can see there are changes in the stripline compared to the TLE1714A. Has anyone successfully modified the TLE1714A to operate on the upper end of the 440 band? Thanks, Louie KA2PFL
[Repeater-Builder] RCA 50 MHz bands (low band) manual needed Series 700 / Series 1000
I am still looking for a service manual / system index for the RCA Series 700 and/or Series 1000 mobile radios in the 50 MHz bands (VHF low band). Any help is appreciated. Please reply to kc5...@yahoo.com Thank You! 73's de KC5DBH Matt
[Repeater-Builder] email for home depot OT
Hi guys This is way over the top..:) but I am trying to purchase a part for the Drill Doctor 750 Professional, and the Home Depot lists as in-stock. Part # required is sa01326ga. I proceeded to the check out basket only to find they have not included Australia in their menu for PnP. Even trying to register hits a brick wall with the same blunder!! Does any kind person have a direct email so that I can address this discrepancy and ask them what freight charges I might be up for? They only want 19.95 US whereas the Ozzies think it's gold plated! Best 73 from downunder John/VK4JKL IRLP 6163
[Repeater-Builder] Re: Can the 4th harmonic of 1250 AM keep UHF repeaters locked up?
Tony, Do you hear a matching signal around the site on 5 MHz? Ron
