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Old October 31st 05, 04:14 PM
Randy or Sherry Guttery
 
Posts: n/a
Default Old Xmtrs, "Ancient Modulation" and Amps

Scott Dorsey wrote:

There are plenty of decent used linear amps out there if you want to go
that route, but if you think about it in dB, 1000W isn't _that_ much
more than 10W.



What??? 10W - 1000W is 20db. Distance doubles every 6db - do the math...

Only a few S-units at the receiver.


Talking about "S-units" in such a discussion is meaningless *unless* one
has checked the calibration of one's meter - AND states the
calibration characteristics to qualify the readings.

The reason is there is no "universal definition or standard" of "S
units". There have been proposals - but so far no standards. The
proposal that seemed to have had the best chance was made in the 40's -
and that was where S9 = 50uv (at the antenna connector) - and each "S
unit" down being -6db. As noted - that never became a standard - in fact
today most modern receivers seem to be around 5db per S unit The reason
seems to be that using -5db/S results in S0 below 50uv being right
around the noise floor of most rigs - i.e. .2uv (S+N/N=10db).

But unless one states what specific characteristics of "S units" they
are using - talking about "S units" is meaningless (i.e. a "few" "S
units" could be 3db - they could be 18db - or more -- who knows if it's
not stated).


sheeesh...
--
randy guttery

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