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"Mark Keith" wrote in message om... "Tarmo Tammaru" wrote in message 275 feet of garden variety RG8Foam would have a loss of about 1.5 db at 10 MHz. LMR400 about 1db. Do NOT use RG213. What's wrong with RG213? It has twice the loss. Tam/WB2TT I show it or regular rg-8 to have only about .2 db more loss per 100 ft than foam rg-8. "10 mhz" So 275 ft would be appx 2.1-2.2 or so db vs the 1.5 db. I would consider twice the loss to be 3 db loss. .6 db should be hardly noticable. MK My chart shows the following loss at 10 MHz:, per 100 feet RG213 0.8db RG8 Foam 0.55 db 9913 0.4 db LMR400 will be marginally better than 9913. By definitin of db, 1 db is the smallest change that is detected by the human ear. 6db is a factor of 4 in power. By twice the loss I meant twice the number of db. This may all be moot, because he is going to have a horrendous SWR on at least one of the bands. I would install two resonant radiators, or some kind of decoupling stubs like the Hygain HT. Tam/WB2TT |
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