John,
You may try and program the repeater to another frequency and see if the problem still there. Some radios will interact with the IF either transmitter or receiver. This may be a long shot but if you are truly at your wits end then give it a look. In scanners they would call these birdies . Since it involves the transmitter I would in the transmit IF chain 1st. Good luck, Robert / KD4PBC From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of John Transue Sent: Sunday, August 31, 2008 4:56 PM To: [email protected] Subject: RE: [Repeater-Builder] Wits End -- Desense Chuck, John Bob, Derek, Eric, Mike, JohnB, and Tom, Thank you all for the helpful suggestions. The connectors appear to be perfect, and they check out with DC. The cable on the RX side is double shielded RG142B/U. The cable on the TX side is not marked with a complete designation. It says AWM Style 1354, but there are many cables that are said to be UL AWM Style 1354. Some of these are 75 ohm, some are 50 ohm. This cable is only six inches long. I plan to replace this as soon as I can get RG400 or other suitable cable. BNC connectors are used on both the RX unit and the TX unit. I don't know what it means to have a feed through capacitor in series with a control or audio or power cable. However, a capacitor to ground might be good to get rid of stray RF. Pray if you are so inclined. Otherwise, hope we can make the physics work. Thanks again, JohnT -----Original Message----- From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of Chuck Kelsey Sent: Sunday, August 31, 2008 3:06 PM To: [email protected] Subject: Re: [Repeater-Builder] Wits End -- Desense I was wondering the same thing. Has someone added some wiring and subsequently breached the integrity of the shielding effectiveness somewhere? First thing to come to mind is controller interfacing and CTCSS wiring. Chuck WB2EDV ----- Original Message ----- From: John J. Riddell <mailto:[EMAIL PROTECTED]> To: [email protected] Sent: Sunday, August 31, 2008 2:43 PM Subject: Re: [Repeater-Builder] Wits End -- Desense John, Make sure that every wire going in to the RX and TX box has a feed thru cap in series with it. Also you might put a few small ferrite beads on each wire as well. John VE3AMZ
