I didn't think there were any vhf stations left. All the numbers on the channels now are virtual. All the tv antenna plans are for uhf bands. A quick look in the Boston market and the lowest channel is 19, channel 2@500MHz. Are there places that still use vhf?
Charles On Dec 7, 2011 1:38 PM, "Bob Bruninga" <[email protected]> wrote: > HPF above 500 MHz? Then the TV would not be able to see anything but a few > UHF channels. > > What is needed is a stub filter. Just a piece of open ended coax 13" long > "T"ed into the antenna lead.... > > The 13" is about 66% of a quarter wave at 2 meters. > > Done > > Bob, WB4APR > > -----Original Message----- > From: [email protected] [mailto:[email protected]] On > Behalf Of Gordon JC Pearce > Sent: Wednesday, December 07, 2011 3:02 AM > To: [email protected] > Subject: [amsat-bb] Re: 2 Meter TV Interference > > On Tue, 6 Dec 2011 21:17:55 -0600 > Wyatt Dirks <[email protected]> wrote: > > > > Just recently I have been having troubles with a neighbor while I am > working the FM satellites(SO-50 and AO-27). The setup I am currently using > is my mobile setup because I am unable to put a base station up for many > reasons. I am using a FT8900 with 50 watts out into a 1/4 wave or 1/2 > Larson > mobile antenna.The 1/4 wave is mounted permanently via a hole in the roof > of > my truck an the 1/2 wave is mounted on a mount opposite the factory > installed FM/AM radio whip. It doesn't seem to matter what antenna I use > for > the problem to occur. Then I use either the arrow antenna or my cju for the > downlink. > > Use 5W into a hand-held Yagi. You'll get far better results. > > > > Today I had another local ham over at the request of the neighbor and his > mobile Kenwood radio did the same thing to the neighbors tv when he > transmitted on 2 meter with 50 watts out. He also recommended that they get > a filter. I did not see the specs on the filter nor do I know what > bandwidth > it was for. > > What you want is a highpass filter that will lop off everything below > 500MHz. The chances are that your TX output is clean enough but the little > amplifier in the splitter for the TV is causing all sorts of intermod - and > probably covers from broadcast VHF radio to the top of the TV band. > > -- > Gordon JC Pearce MM0YEQ <[email protected]> > _______________________________________________ > Sent via [email protected]. Opinions expressed are those of the author. > Not an AMSAT-NA member? Join now to support the amateur satellite program! > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb > > _______________________________________________ > Sent via [email protected]. Opinions expressed are those of the author. > Not an AMSAT-NA member? Join now to support the amateur satellite program! > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb > _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
