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On Sun, 29 Apr 2012 16:24:52 -0600, "Irv Finkleman"
wrote: I have an MFJ-259B -- couldn't live without it, and with all the stuff I gave away this was the one thing that I just couldn't part with. For when you transmit into it by accident... http://802.11junk.com/jeffl/pics/2011-12-03-Storm/ The MJF-259B is similar to the MFJ-269B, except that it lacks the 440MHz section. It's a very handy instrument, but is rather fragile in that the detector diodes are connected directly to the RF connector. One blast of too much RF, too much static electricity, or even too much DC, and the diodes go poof. Good move! I've always maintained that if you give me any old piece of metal almost anywhere, I'd find a way to load it and get on the air! There's also the rain gutters. This case now though, is the first time I ever went into a place that seemed impervious to signals. I've often operated from indoors with no problem, and here, the first time I flashed up the receiver, thought it had gone dead -- that's how bad it was. The first thing I did was checked the protective diodes on the antenna connector and as soon as I found them OK, opened the window and strung a short wire outside -- then everything was 5/9 plus! Welcome to the joys of modern energy efficient construction. The walls are full of aluminum foil backed insulation for both thermal and acoustic insulation. The windows are coated with Low-E Titanium Nitride IR reflective coatings (40 ohms per square), which also blocks RF. The roofing material is carbon doped (instead of asbestos) which absorbs RF. The foundation is concrete, which also absorbs RF. Meanwhile, the proliferation of microprocessors, switching power supplies, and BPL like devices, offers multiple sources of QRN. You had it easy at previous locations. As per another sailor many years ago said, 'I have not yet begun to fight!' Fighting is easy. It's negotiation that drives me nuts. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
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