In the discussion of line and tuner losses, Ward wrote...
> 30% sounds like a lot, but it's only 1.55 dB. Not to be ignored, by any
> means, but not a brutal signal reduction. 0.5 dB is about 10% signal
> loss.
It seems we often get fooled by such things. I remember acquiring a
bunch of old but apparently good RG8 coax. Before I ran it "up the
tower" I decided to test it at 29MHz. I put a dummy load on one end,
and my Bird 43 and transceiver on the other end. I sent 100W down
the line (I couldn't measure any Watts coming back). Then I moved
the Bird to the dummy load end, and keyed up. Only 85 watts were
making it down there! "That's a fifteen percent loss! This stuff is
junk!" I then checked the manufacturer's specifications... the coax
was in spec. for NEW cable!
Fifteen percent = about 0.7 db loss for however many feet I had.
Gee, 0.7 db doesn't sound like as much as 15%!
73,
George T. Daughters, K6GT
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