Happy 2005 to all, Allow me to ask: is this windom the Windom's wire windom or some of the later modified windoms?Then why resonant antennas are not necessary allthough convenient? 73 Chris Papaioannou SV1DAF. ----- Original Message ----- From: "Donald Chester" <[EMAIL PROTECTED]> To: <[email protected]>; <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]> Sent: Monday, December 27, 2004 3:27 AM Subject: RE: [AMRadio] RE: GB> Antenna Tuner Wonderings
> > > >From: "Merz Donald S" <[EMAIL PROTECTED]> > >Reply-To: Discussion of AM Radio <[email protected]> > >To: "Bob Macklin" > ><[EMAIL PROTECTED]>,<[EMAIL PROTECTED]>,"'Amradio > >(E-mail)" <[email protected]> > >Subject: [AMRadio] RE: GB> Antenna Tuner Wonderings > >Date: Tue, 14 Dec 2004 11:14:24 -0500 > > > >Thanks for your reply. > > > >OK, Yes, I understand. Some of the rigs here are homebrew and the output > >network designs are all over the lot. On the antenna side, there are > >situations here like a vertical with a poor counterpoise that will have 25 > >or 30 ohms to match at some frequencies. Then there's the Windom, which > >isn't resonant anywhere. IMHO, resonant antennas are convenient, but > >certainly not necessary (thank God). > > > >73, Don Merz, N3RHT > > > > > >-----Original Message----- > >From: Bob Macklin [mailto:[EMAIL PROTECTED] > >Sent: Monday, December 13, 2004 5:56 PM > >To: Merz Donald S; [EMAIL PROTECTED]; 'Amradio (E-mail) > >Subject: Re: GB> Antenna Tuner Wonderings > > > > > >With BA unit wit Pi networks you don't need a TransMatch (they ARE NOT > >antenna tuners). Most will match anything between 50 and about 500 ohms. > >One > >exception is the Heath DX-60. It is limited to 50 to 75 ohms becase of the > >built in LP filter. > > > >You need a resonant antenna for each band you want to work. Some could be > >multi band antennas. > > > >A TransMatch does not correct antenna problems. It hides them from the > >transmitter. The Pi network in the BA rigs is the same thing that was in > >older transmatches to connect link couples transmitters to coax lines. > > > >It is the solid state riceboxes that really need a transmatch. > > > >Bob Macklin > >K5MYJ/7 > >Seattle, Wa. > > > >"REAL RADIOS GLOW IN THE DARK" > > > > > > > >----- Original Message ----- > >From: "Merz Donald S" <[EMAIL PROTECTED]> > >To: <[EMAIL PROTECTED]>; "'Amradio (E-mail)" > ><[email protected]> > >Sent: Monday, December 13, 2004 2:23 PM > >Subject: GB> Antenna Tuner Wonderings > > > > > > > As most of you know, I am a long time BA collector and inexperienced > >operator. I am getting there. But it's a learning process <grin>. > > > > > > I have the shack structured (in the loosest sense of the word...) into a > >number of stations (20-25 with about 10 in actual operation). These mostly > >consist of a transmitter/receiver pair with T/R relay and RX muting. The > >stations are in the range of 40 to 250 watts max. I run these into your > >choice of 5 or 6 crappy, mostly non-resonant antennas with connections > >being > >made through a home-made SO-239 "patch panel". > > > > > > Most of my interest is in AM operation on or near the supposed "AM > >windows" on 80, 40 and 20. I have some rigs that I never change bands on. > >My > >operation is often xtal-controlled but I have VFOs on some of the rigs. > >Most > >of these old BA transmitters are pi-net outputs. > > > > > > So here's the deal: I can tune any of these stations into a 52 ohm dummy > >load and set up the rig easily enough. Now I switch to one of my crappy > >antennas. And of course, it is nowhere near 52 ohms at the desired > >operating > >frequency. If the mismatch isn't too bad, I can re-tune the rig's output > >network. If the mismatch is ugly, or if the output network is limited in > >range, then I can "insert antenna tuner here" to get a match. > > > > > > After a while, laziness sets in. Why should I have an antenna tuner for > >each rig?--especially if I never change bands on that rig? Wouldn't it make > >more sense to dedicate an antenna tuner to each antenna? I can use my > >little > >Palomar Tuner Tuner to match to pre-set each antenna to 52 ohms for each > >frequency of interest and mark each antenna tuner accordingly. Then I can > >simply load the rig up for 52 ohms into a dummy load, select an antenna, > >set > >the antenna tuner to my previously-marked 52 ohm point for that frequency > >on > >that antenna, patch the rig into the antenna tuner--and push-to-talk. > > > > > > Ok, sure, this setup put the antenna tuner over at the patch panel and > >not > >on top of the rig. Pretty inconvenient. But hey, there's 20-25 stations to > >deal with here. I'm supposed to have 25 antenna tuners? OTOH, I have only 3 > >antennas that are sloppily non-resonant enough to require a tuner at the > >frequencies I am interested in. So that's 25 tuners (okay, I'm > >exaggerating--it would probably be only 10-15 tuners because the other > >stations probably have adequate output networks) versus just 3. > > > > > > This trade-off seems worth it to me. But experience is in short supply > >here. So "pray tell me"** experienced ones, what am I missing? What is > >there > >about this idea that is bad? > > > > > > Any thoughts appreciated. > > > > > > 73, Don Merz, N3RHT > > > > > > ** When Winston Churchill was named First Lord of the Admiralty in 1939, > >he was famous for firing off memos with questions to subordinates that > >began > >"Pray tell me...". In the Royal Navy, these soon became known, obviously, > >as > >"the Lord's prayers". > > > > > > The information contained in this e-mail may be confidential and is > >intended solely for the use of the named addressee. > > > Access, copying or re-use of the e-mail or any information contained > >therein by any other person is not authorized. > > > If you are not the intended recipient please notify us immediately by > >returning the e-mail to the originator.(A) > > > > > > >The information contained in this e-mail may be confidential and is > >intended solely for the use of the named addressee. > >Access, copying or re-use of the e-mail or any information contained > >therein by any other person is not authorized. > >If you are not the intended recipient please notify us immediately by > >returning the e-mail to the originator.(A) > >______________________________________________________________ > >AMRadio mailing list > >Home: http://mailman.qth.net/mailman/listinfo/amradio > >Help: http://mailman.qth.net/mmfaq.html > >Post: mailto:[email protected] > > > ______________________________________________________________ > AMRadio mailing list > Home: http://mailman.qth.net/mailman/listinfo/amradio > Help: http://mailman.qth.net/mmfaq.html > Post: mailto:[email protected] >
