[Repeater-Builder] White Noise on Micor TX
I have a small amount white noise on the TX of a Micor repeater. It is most noticeable in the hang time but it's not coming from the controller. It's still there with the controller completely removed and pressing PTT on the station control card. It's more noticeable on some radios, perhaps radios with higher audio frequency response. Anyone ever run into this before? Tim WD6AWP
Re: [Repeater-Builder] Micor CA info - seeking
Because of the limited amount of storage space Yahoo allows for group files, you will find FAR more information on the Repeater-Builder website than in the Yahoo group files. Start here: http://www.repeater-builder.com/micor/ George, KA3HSW / WQGJ413 - Original Message - From: "Kuby" To: Sent: Saturday, May 22, 2010 11:08 AM Subject: [Repeater-Builder] Micor CA info - seeking Try this again, my first posting never got posted. I did a MSG search on Micor and got no where. I want to the FILES area and found no Motorola Folder or anything else for Micor or GE. The FILES area needs some serious re-org/grouping to make finding easier! Or what did I do wrong in my searching of this group?
Re: [Repeater-Builder] Re: GMRS repeater wanted or parts to build one
Brian, I will contact you off list re: a repeater I have that would fit your bill perfectly. -Brian On Thu, May 20, 2010 at 5:38 AM, Brian wrote: > > > Yes, I do, but I need one in a different location. There are allot of hiss > around here. > > > - Original Message - > *From:* kc7stw > *To:* Repeater-Builder@yahoogroups.com > *Sent:* Thursday, May 20, 2010 3:13 AM > *Subject:* [Repeater-Builder] Re: GMRS repeater wanted or parts to build > one > > > > You do know there is one on the air now right! > > Contact off list... > > --- In Repeater-Builder@yahoogroups.com, "ke7wrc" wrote: > > > > Hi, I am new to this group. I was wondering if anyone had a working used > repeater for sale that I could use for GMRS or help in finding parts etc. to > build my own. I would need everything including the cabinet, radio(s), > controller, duplexer, antenna(s), and maybe even power supply. I would > probably need to purchase liability insurance also, so any help with > insurance providers, policy limits and customary insurance premiums would be > of help as well. I live in the Reno/Sparks, Nevada area. Thank you for your > time and help! > > > > Brian Becker > > KE7WRC > > WQDX970 > > > > > >
Re: [Repeater-Builder] Crossband Repeater - Desense? High Pass Filter Needed?
A few questions to which the answers would be extremely helpful: * What are the frequencies in question? * Are they harmonically related? * How much vertical separation is there between the two antennas on the tower? * Are they directly one above the other? * What is the gain of the two antennas? * Which band is on the top? * Did the system *ever* work without desense, or has something changed? If something has changed: * Are the antennas and feedlines visibly OK? * What sort of feedline is being used? 9913? * Any new neighbors on the hill? * Any recent lightning? A low-pass filter on the LB Tx may help. It could be the harmonics of the LB Tx clobbering the VHF Rx. Have you looked at the output of the LB Tx on a spectrum analyzer in the VHF area? Some (Motorola Micor) LB Tx's have a low-pass filter *after* the PA and before the antenna output. Does your Midland have something similar? This would definitely help suppress the harmonics. If your Midland doesn't seem to have a LPF after the PA and the spectrum analyzer shows lots of noise in the VHF area, I would get a hold of a Micor LB LPF and put it in series and see if that helps. They are designed to be 50 ohms in /out and are rated for 100W or so. Scott Scott Zimmerman Amateur Radio Call N3XCC 474 Barnett Road Boswell, PA 15531 tritium242 wrote: > Hello all. We have a cross band repeater (Midland 100W VHF low w/ 1W VHF high > band repeater built in). > > What we noticed is that in the High Band --> Low Band direction, the high > band side will receive the signal, then the low band Tx will key up to repeat > the signal. Normally, all works just fine. But at extended distances, the low > band TX keying up will deafen the high band side trying to copy the faint > signal (from an HT), resulting in a choppy, unintelligible signal at the max > distance. > > This is only with a faint/distant enough signal, like a HT at a distance. In > the other direction (low band --> high band), there is a HUGE increase in > maximum distance, even with just 1W from the high band Tx going out, since it > seems to be not enough power to desense the low band Rx. > > Long story short, will adding a high pass filter to the high band side to > shield the high band Rx from the powerful low band Tx do the trick? Where can > one find such a thing? It just has to pass from say, 100-120 Mhz, and block > everything below it, and tolerate 1W of Tx power is all. > > We'd like to avoid using a big, bulky cavity filter if possible, since we > don't need monster isolation figures, or high power handling capabilities. > Thanks in advance for any ideas! > > > > > > > > Yahoo! Groups Links > > > >
Re: [Repeater-Builder] Crossband Repeater - Desense? High Pass Filter Needed?
You might want to post the frequencies. Chuck WB2EDV - Original Message - From: "tritium242" To: Sent: Saturday, May 22, 2010 3:30 PM Subject: [Repeater-Builder] Crossband Repeater - Desense? High Pass Filter Needed? > Hello all. We have a cross band repeater (Midland 100W VHF low w/ 1W VHF > high band repeater built in). > > What we noticed is that in the High Band --> Low Band direction, the high > band side will receive the signal, then the low band Tx will key up to > repeat the signal. Normally, all works just fine. But at extended > distances, the low band TX keying up will deafen the high band side trying > to copy the faint signal (from an HT), resulting in a choppy, > unintelligible signal at the max distance. > > This is only with a faint/distant enough signal, like a HT at a distance. > In the other direction (low band --> high band), there is a HUGE increase > in maximum distance, even with just 1W from the high band Tx going out, > since it seems to be not enough power to desense the low band Rx. > > Long story short, will adding a high pass filter to the high band side to > shield the high band Rx from the powerful low band Tx do the trick? Where > can one find such a thing? It just has to pass from say, 100-120 Mhz, and > block everything below it, and tolerate 1W of Tx power is all. > > We'd like to avoid using a big, bulky cavity filter if possible, since we > don't need monster isolation figures, or high power handling capabilities. > Thanks in advance for any ideas! > > > > > > > > Yahoo! Groups Links > > > No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.819 / Virus Database: 271.1.1/2890 - Release Date: 05/22/10 14:26:00
Re: [Repeater-Builder] Micor CA info - seeking
Not sure what exactly you are looking for. Have you been here: http://www.repeater-builder.com/rbtip/ Chuck WB2EDV - Original Message - From: "Kuby" To: Sent: Saturday, May 22, 2010 12:08 PM Subject: [Repeater-Builder] Micor CA info - seeking > Try this again, my first posting never got posted. > > I did a MSG search on Micor and got no where. I want to the FILES area and > found no Motorola Folder or anything else for Micor or GE. The FILES area > needs some serious re-org/grouping to make finding easier! > > Or what did I do wrong in my searching of this group? > > > > > > > > Yahoo! Groups Links > > > No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.819 / Virus Database: 271.1.1/2890 - Release Date: 05/22/10 14:26:00
[Repeater-Builder] Micor CA info - seeking
Try this again, my first posting never got posted. I did a MSG search on Micor and got no where. I want to the FILES area and found no Motorola Folder or anything else for Micor or GE. The FILES area needs some serious re-org/grouping to make finding easier! Or what did I do wrong in my searching of this group?
Re: [Repeater-Builder] Need source for UHF power module
there is a company here in New Zealand that used to or maybe still does deal with Kenwood products http://www.pacificaerials.co.nz/ I know of no one else, other than Kenwood themselves Marcus On Sat, May 22, 2010 at 5:02 PM, byronhham wrote: > > > Hi > Does anyone know of a good source for a M57729h-01-p. > > It is the UHF power module in the Kenwood TKR-820. > > It is rated at 30 Watts 12 volts 440 to 470 MHz. > > I found that they do not like to be operated into the wrong side of a > duplexer. For even a short time. > > Is it used in any other transceivers that might be purchased for the > module? > > Thanks > Byron NJ7J > > >
[Repeater-Builder] Crossband Repeater - Desense? High Pass Filter Needed?
Hello all. We have a cross band repeater (Midland 100W VHF low w/ 1W VHF high band repeater built in). What we noticed is that in the High Band --> Low Band direction, the high band side will receive the signal, then the low band Tx will key up to repeat the signal. Normally, all works just fine. But at extended distances, the low band TX keying up will deafen the high band side trying to copy the faint signal (from an HT), resulting in a choppy, unintelligible signal at the max distance. This is only with a faint/distant enough signal, like a HT at a distance. In the other direction (low band --> high band), there is a HUGE increase in maximum distance, even with just 1W from the high band Tx going out, since it seems to be not enough power to desense the low band Rx. Long story short, will adding a high pass filter to the high band side to shield the high band Rx from the powerful low band Tx do the trick? Where can one find such a thing? It just has to pass from say, 100-120 Mhz, and block everything below it, and tolerate 1W of Tx power is all. We'd like to avoid using a big, bulky cavity filter if possible, since we don't need monster isolation figures, or high power handling capabilities. Thanks in advance for any ideas!
[Repeater-Builder] Re: Duplexer on the cheap worries
Thanks for the replies. I don't have the high end equipment to do some of the testing mentioned. I do have a service monitor and a dummy load, along with numerous receivers. The dummy load is kind of suspect (old and not really liking the strange signals I get from it at times) but it is all we can find around here right now. That is how I was setting it up first. I have tried the dummy load but me and friend were playing with the repeater with the load installed and got all sorts of noise and things. So we thought putting it on an antenna would be a better test. I did do some cable swapping and fed the signal from the TX to the service monitor (connected on the RX port of the Duplexer) with the antenna connected. The cables I had hooked to the Tee were the 1/2 wavelength rg-142. I replaced them, for testing purposes, with shorter runs of rg-213, approx. 1/4 wavelength. The signal on the service monitor, went away completely. No power or signal on the meter. With the longer cables I had no power but a jumping signal on the service monitor. I have some 214 I will be making the inter connect cables out of when I get things nailed down a bit more. Someone asked the freq. and spacing earlier, it is 145.340 TX and 144.74 RX (Typical 600KHz split). My friend had talked to some radio shop around here and they said RG-8 and LMR-400 were fine just keep them from moving around. I do plan on using 1/2" hardline and some superflex jumpers out at the site. Thanks for the help so far. Any other suggestions now? Wade KC0MLT --- In Repeater-Builder@yahoogroups.com, wd8chl wrote: > > On 5/21/2010 10:28 AM, kc0mlt wrote: > > Hello all. > > > > I am trying to figure out if the duplexer we have put together is up > > to the task or not. Here is the situation. We have four cavities 6.5" > > dia. one is a vari-notch the others are simple reject cans. Two > > rejects are on the TX side and one reject and the vari-notch are on > > the RX side. All set and tuned with rg-213 jumpers between cans and > > RG-142 from the cans to the Tee connector. We are doing some light > > testing with a cheap dual ban antenna on the garage. It is feed with > > RG-8 about 70 feet. We are having some issues with receive. It kind > > of sounds like desense but I think it is something wrong with the > > receiver. I was just wondering if the cobbeled together cans sound > > like thay are doing a good enough job as a duplexer or if we do have > > something to change on it. The repeater is only putting out 2 watts > > for testing. I would think I have enough separation for that power > > level. Any suggestions or thoughts woyuld be greatly appreciated. > > > > Thanks Wade KC0MLT > > Dump the RG-213 and RG-8 and use at least RG-214 between cavities, or > 1/2" hardline on the run up to the antenna. > RG-8 and -213 are single shielded and do not provide adequate isolation. > You need 100% shielding. > Also find a GOOD dummy load, and substitute that in place of the > antenna. If you still have the problem, there is an antenna issue. >
RE: [Repeater-Builder] Lost 10 volts in a Master II UHF Repeater
This is also a good place for the 'finger test'. If there are suspect components you can get to that can't easily be removed (by pulling boards, etc.) then a calibrated finger will often lead you to the defective component. If it's really a cap, it should be generating a lot of heat. Sometimes your nose is a good indicator of what's getting hot too, but you really don't want to be sniffing the cap when the purple smoke and sparks decide to leak out! Every Tech Order I ever used in the Air Force started with 'Perform a through visual inspection'. Often times, that was good advice. 73, Mike WM4B From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Eric Lemmon Sent: Saturday, May 22, 2010 10:48 AM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Lost 10 volts in a Master II UHF Repeater Whenever you have a shorted component, such as a tantalum capacitor, the current drawn by that short might burn out a PC board trace before burning up the capacitor. If that happens, finding the original problem becomes much more difficult. Perhaps a better and safer tack would be to use a small current-limited power supply to energize the 10 volt buss, but with the current limit set to 1/4 ampere or so. Following Jeff's suggestion, start unplugging and/or disconnecting loads until the buss voltage jumps up to 10 volts. I don't know what current is normally drawn from the 10 volt regulator in a properly-operating station, but that value should be measured and recorded for future troubleshooting efforts. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Jeff DePolo Sent: Saturday, May 22, 2010 6:36 AM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Lost 10 volts in a Master II UHF Repeater > I would look for a shorted tantalum capacitor hanging > somewhere on the > 10V rail. I agree. > If you hook 10V from an outside source to the 10V > buss, you'll > probably find it's drawing all kinds of current. The 10V regulator > circuit will go into fold back before burning up. This is by > design. I > usually hook a source of 10V at about 1.5A and look for smoke. It's > usually one of the tantalum capacitors that starts to smoke. > Once it's > done smoking, problem solved!! Put a DMM on the 10V line, then start disconnecting things until you narrow it down, divide and conquer. Pull all of the cards out of the cage (except the 10V reg card obviously), disconnect the exciter, remove the receiver, etc. With a good ohmmeter that measures fractions of an ohm, you should be able to narrow it down further once you've found the suspect module/board. > I have lost track of how many shorted tantalums I have had over the > years. When they occur in the B+ of the high current PA supply, they > simply burn up and th problem fixes itself. They make a cool purple smoke with lots of sparks when they flame out! --- Jeff WN3A
Re: [Repeater-Builder] Lost 10 volts in a Master II UHF Repeater
At 5/22/2010 07:28, you wrote: >On Sat, 22 May 2010, Chuck Kelsey wrote: > > And sometimes scare the crap out of you! And they stink. > > > > > > They make a cool purple smoke with lots of sparks when they flame out! > >IIRC they contain an element you're not supposed to breathe because it >only causes cancer in the state of California. I thought they were perfectly safe because there's no prop. 65 warning label on the radio ;) Bob NO6B
RE: [Repeater-Builder] Lost 10 volts in a Master II UHF Repeater
Whenever you have a shorted component, such as a tantalum capacitor, the current drawn by that short might burn out a PC board trace before burning up the capacitor. If that happens, finding the original problem becomes much more difficult. Perhaps a better and safer tack would be to use a small current-limited power supply to energize the 10 volt buss, but with the current limit set to 1/4 ampere or so. Following Jeff's suggestion, start unplugging and/or disconnecting loads until the buss voltage jumps up to 10 volts. I don't know what current is normally drawn from the 10 volt regulator in a properly-operating station, but that value should be measured and recorded for future troubleshooting efforts. 73, Eric Lemmon WB6FLY -Original Message- From: Repeater-Builder@yahoogroups.com [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Jeff DePolo Sent: Saturday, May 22, 2010 6:36 AM To: Repeater-Builder@yahoogroups.com Subject: RE: [Repeater-Builder] Lost 10 volts in a Master II UHF Repeater > I would look for a shorted tantalum capacitor hanging > somewhere on the > 10V rail. I agree. > If you hook 10V from an outside source to the 10V > buss, you'll > probably find it's drawing all kinds of current. The 10V regulator > circuit will go into fold back before burning up. This is by > design. I > usually hook a source of 10V at about 1.5A and look for smoke. It's > usually one of the tantalum capacitors that starts to smoke. > Once it's > done smoking, problem solved!! Put a DMM on the 10V line, then start disconnecting things until you narrow it down, divide and conquer. Pull all of the cards out of the cage (except the 10V reg card obviously), disconnect the exciter, remove the receiver, etc. With a good ohmmeter that measures fractions of an ohm, you should be able to narrow it down further once you've found the suspect module/board. > I have lost track of how many shorted tantalums I have had over the > years. When they occur in the B+ of the high current PA supply, they > simply burn up and th problem fixes itself. They make a cool purple smoke with lots of sparks when they flame out! --- Jeff WN3A
Re: [Repeater-Builder] Lost 10 volts in a Master II UHF Repeater
On Sat, 22 May 2010, Chuck Kelsey wrote: > And sometimes scare the crap out of you! And they stink. > > > > They make a cool purple smoke with lots of sparks when they flame out! IIRC they contain an element you're not supposed to breathe because it only causes cancer in the state of California. -- Kris Kirby, KE4AHR Disinformation Analyst
Re: [Repeater-Builder] Lost 10 volts in a Master II UHF Repeater
And sometimes scare the crap out of you! And they stink. Chuck WB2EDV - Original Message - From: "Jeff DePolo" To: Sent: Saturday, May 22, 2010 9:35 AM Subject: RE: [Repeater-Builder] Lost 10 volts in a Master II UHF Repeater > > They make a cool purple smoke with lots of sparks when they flame out! > > --- Jeff WN3A
RE: [Repeater-Builder] Lost 10 volts in a Master II UHF Repeater
> I would look for a shorted tantalum capacitor hanging > somewhere on the > 10V rail. I agree. > If you hook 10V from an outside source to the 10V > buss, you'll > probably find it's drawing all kinds of current. The 10V regulator > circuit will go into fold back before burning up. This is by > design. I > usually hook a source of 10V at about 1.5A and look for smoke. It's > usually one of the tantalum capacitors that starts to smoke. > Once it's > done smoking, problem solved!! Put a DMM on the 10V line, then start disconnecting things until you narrow it down, divide and conquer. Pull all of the cards out of the cage (except the 10V reg card obviously), disconnect the exciter, remove the receiver, etc. With a good ohmmeter that measures fractions of an ohm, you should be able to narrow it down further once you've found the suspect module/board. > I have lost track of how many shorted tantalums I have had over the > years. When they occur in the B+ of the high current PA supply, they > simply burn up and th problem fixes itself. They make a cool purple smoke with lots of sparks when they flame out! --- Jeff WN3A
Re: [Repeater-Builder] Need source for UHF power module
Check with RF Parts (www.rfparts.com). Years ago I purchased a power module for an IC-2710H Icom and it was about half the price than Icom. From: byronhham To: Repeater-Builder@yahoogroups.com Sent: Sat, May 22, 2010 12:02:08 AM Subject: [Repeater-Builder] Need source for UHF power module Hi Does anyone know of a good source for a M57729h-01-p. It is the UHF power module in the Kenwood TKR-820. It is rated at 30 Watts 12 volts 440 to 470 MHz. I found that they do not like to be operated into the wrong side of a duplexer. For even a short time. Is it used in any other transceivers that might be purchased for the module? Thanks Byron NJ7J
