I would strongly suspect that new preamp to be the culprit.
73 Gary K4FMX _____ From: Repeater-Builder@yahoogroups.com [mailto:[EMAIL PROTECTED] On Behalf Of Nate Duehr Sent: Saturday, February 03, 2007 2:35 PM To: Repeater-Builder@yahoogroups.com Subject: Re: [Repeater-Builder] Intermod On 2/3/07, Jeff DePolo <[EMAIL PROTECTED] <mailto:jeff%40depolo.net> net> wrote: > > I think I see how Steve's logic is leaning, and I agree - I don't see any > logical mix here until you include a user's transmission on one of the > repeater's inputs. Fred - do you hear ALL 147.33 transmitter activity > coming in on the 147.765 input, or just when there is actually a user keyed > up on 147.93? If the latter, that's a big clue... > > --- Jeff Yep, that's going to be the key... been there done that... Ye olde 600 KHz split on VHF problem. It creates perfect mixes with users and the repeaters themselves that fall right smack on the input of the next repeater along the band. A close-in high-powered user to a VHF repeater can mix with it with bad results for the next in line machine. Requiring CTCSS on a different tone than the original machine and users will cover up the problem, but not fix it, of course... not a permanent fix, but sometimes necessary. If Jeff's observation is correct, and you only hear input activity... try to find a ham who's rig causes the issue consistently (and you'll probably find that HT users don't, also -- they're usually just too weak to create a strong-enough mix). Then you can have that person lower their power and see if the problem signal on the repeater's input seems to drop out quickly or get much weaker, since you're looking for a mix that would drop off rapidly as one of the transmitter's power levels was lowered. If that's not it... have a 600 KHz AM station in your town? There's always the possibility of other mixes as well... Jeff's test is the kicker to start with -- do you hear the full TX tail of the other repeater or just user input? Does it do it on ALL transmissions or just certain users? Anyone involved in the situation live real close to either repeater, who you know has high gain antennas and runs lots of power? Nate WY0X
