I had a problem like this but it was all the time and it was caused by a faulty matv amplifier in a apartment building a block away from the repeater. It cause the rooftop TV antenna connected to the matv amp to radiate. A now retired and possibly deceased FCC examiner out of the Dallas field office made a trip to our town at the request of our ham club and he tracked the problem down and made the owner of the matv system shut their equipment down until it could be repaired A low band TV antenna amp going into oscillation can cause a lot of problems on 6 meters. BTW a first phone tech who installed the matv unit argued with the FCC inspector and got his license revoked in the process. Sometimes it is best do what you are told and fix it later! wb5oxq.
----- Original Message ----- From: neal Newman To: [email protected] Sent: Friday, December 26, 2008 8:39 AM Subject: Re: [Repeater-Builder] Six Meter Repeater Noise Issues Noise on the six meter repeater. On my machine 53.67 in New jersey I was getting noise that was holding the machine Keyed up. then drop. and key up again. I thought it was desense Even with a big expensive Commercial Duplexer. with the transmitter off, the normal unsquelched Hiss sounded Fine No noise that we could detect. after weeks of this. We finally found out what the Problem was. the 2 meter,and 440 machines next to it ran just fine.however They both had an IRLP link on them. The Noise problem turned out to be the Router/switch. The Noise it was creating was just at the threshold level to Key and hold open the repeater. BTW. The 6 meter machine was in PL with a Tone of 67hz...... Not a good choice. between the60 cycle noise of a bad wall wart for the router switch and the noise it created. might as well put a flea power transimitter with PL sitting on the repeaters input. changed the router swich and PL tome. and Problem wentt away. Verizon uses cheapo routers. we placed the new one in a shielded box Neal-KA2CAF --- On Thu, 12/25/08, Mike Morris WA6ILQ <[email protected]> wrote: From: Mike Morris WA6ILQ <[email protected]> Subject: Re: [Repeater-Builder] Six Meter Repeater Noise Issues To: [email protected] Date: Thursday, December 25, 2008, 10:12 PM At 11:06 AM 12/25/08, you wrote: Hi To All & Hope everybody had a good Christmas, While the subject was brought up, I have been having a similar experience here at my location. It is not on a repeater, but a simplex radio (vertex VX3000l mobile) for a base on the natl Red Cross freq of 47 mhz. In the daytime the receiver is quiet and hears fine. It seems as about the time the sun starts going down, the receiver's squelch opens and has a constant static noise for many hours but still receives fine. It may do it all night, I don't know, I haven't stayed up to see, just leave the radio on and go to bed. Was wondering if could be power line noise (but why wouldn't do in daytime also)? Is there any interference to the HF bands like this at night? Thanks, Mike KB5FLX An old trick - if the on-time changes about 6 minutes a day then it's light-dependent (i..e a photo-electric triggered yard light). In your shoes I'd power the radio from a gell-cell, and then go flip breakers off one at a time. That will tell you if the noise source is inside the house, and if so, on which breaker. Mike WA6ILQ
