View Single Post
  #20   Report Post  
Old February 6th 04, 04:18 PM
Tarmo Tammaru
 
Posts: n/a
Default


"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