CATV can have leakage from 11 MHz (DCT return carrier) clear up to above 1100 MHz (digital video/data carrier)...
CATV leakage a lot of the time in our experience has been the in home wiring that is either using poorly shielded cable (i.e. RG59 or Lowes/Home Depot RG6 or anything from Rat Shack) or has poor cable terminations (crimped on fittings with pliers, any twist on fittings, gold plated anything (especially splitters), etc... While CATV does cause inference if leakage occurs, our larger bandit, at least in SW Idaho, is commercial power (Idaho Power Co)... It's amazing how loud of a noise carrier a bad transformer can cause on a site... 73s, AJ, K6LOR On Wed, Jan 28, 2009 at 7:04 AM, Mike Wehr <weh...@comcast.net> wrote: > Cable television at your QTH? > > Cable can have some leakage... 145mhz area. > > 73 de Mike, KO9I > > ----- Original Message ----- > *From:* Christopher K. Greenhalgh <ch...@n8wct.com> > *To:* Repeater-Builder@yahoogroups.com > *Sent:* Monday, January 26, 2009 2:24 PM > *Subject:* [Repeater-Builder] 2 meter noise help! > > While not a true repeater, I hoping the gurus here can help me. > > Station info can be seen here; http://www.n8wct.com/n8wct-4/ > > The noise is a subtle low-frequency "bacon crackling". It is apparent > across the whole 2 meter band. Every piece of (my) equipment has been > replaced, or substituted. We even bypassed the filter, turned everything > off, and the noise was still present, even on battery power. SWR is > fine...the station can be heard 90 miles away. > > Even though the noise is subtle, the "pops" seem to be on frequency with > the packet tones, thus, the radio requires an S8 strong receive signal, > before the TNC can decode it! > > We are pretty sure its environmental...perhaps one of the large roof fans, > a/c unit, or crap from the large adjacent electrical room...whatever it is, > we are guests on the building, and probably would get much sympathy/help > from the owners. > > Here's where I need help... > > 1. Identifying the source. I have an o-scope, but frankly, don't know much > about how to use it. Is there some sort of antenna analyzer that would help > me with this? Any other comments or advice would be deeply appreciated. > > 2. Repair or eliminate source. > > Or 3. If I cant repair or eliminate the source, is there a way to filter it > out? > > This is really a great location, and I'm very eager to remedy the problem, > so if anybody has anything...anything at all, please share. > > Thanks everyone. > > 73, Chris. > > _________________________________ > Chris Greenhalgh, N8WCT > > www.n8wct.com > > > >
