Bob, Yes, I think you could put at receiver and your directional coupler would offer a better match for all including the sig gen and would not have to deal with the tx power. The main thing is to see how any noise would affect the receiver.
Ch 2-6 will not go dead in Feb 2007. Some stations will turn off their analog txs and use what they are now using for HDTV probably on UHF, but many will turn off the HDTV and convert their analog VHF, lo and hi, to HDTV on these lower channels. Our ch 3, EDU educational will do this. It is the only local lo VHF. All the high VHF here will convert to HDTV and turn off what is now their UHF HDTV. $1,000,000 being turned off to set. 73, ron, n9ee/r >From: [EMAIL PROTECTED] >Date: 2008/07/10 Thu AM 10:03:26 EDT >To: [email protected] >Subject: Re: [Repeater-Builder] Measuring Desense > >At 7/10/2008 00:55, you wrote: > >>At 12:18 PM 07/09/08, you wrote: >> >>><<...>> Ron, Don, Mark, and others, >>> >>>The attachment shows how I think I should connect things to measure >>>desense. I would use the Bird with sampling coupler in place of the iso >>>tee shown. Does this appear to be a correct way to measure desense? >>> >>>Also, I can replace the feed line and antenna with a dummy load as Ron >>>has explained. >>> >>>John AF4PD >> >>< http://www.repeater-builder.com/tech-info/effectivesens.html> >> >>Mike WA6ILQ > >Somehow I thought Jeff D. originally wrote this; I stand corrected. > >I use a 20 dB directional coupler instead of the iso-T, & place it in front >of the RX instead of in the antenna line. Any reason why this method would >be less effective? The coupler's going to have a bit of loss compared to >the iso--T, but should be under a dB. > >Regarding the "note" at the end of the article: TV 2, 4 & 5 will go dark at >the analog/DTV cutover in Feb. 2009. Ironically, 6 meters may become less >noisy on Mt. Wilson than UHF. :( > >Bob NO6B > > > Ron Wright, N9EE 727-376-6575 MICRO COMPUTER CONCEPTS Owner 146.64 repeater Tampa Bay, FL No tone, all are welcome.
