[Elecraft] Linear thoughts

[Edward R Cole]

George,

My Harris Platinum-1 (ch. 2 TV) linear runs 1000w output for 11w 
drive which is 19.6 dB gain.  But this is on 6m which I do not 
believe is restricted to 15-dB gain by the FCC.  My understanding 
that this rule just affected HF amplifiers.  In any case it is 
legally built under FCC rules for television and is modified for use 
by hams on 6m or higher bands.  There is no rule restricting you 
building a ham amplifier with more than 15-dB (only applies to 
manufacturers who sell to the public).

In fact, I can build such an amplifier and sell it legally to another 
ham, as long as I am not a business doing  multiple sales per year.

I built several linear amps for 2m that produced 80w output with as 
little drive as 50mw.  They are biased to draw 8A quiescent current 
(about 15A at 80w  output), so  this is near to class-A.  I have some 
50w linear amps for 3400-MHz that draw full current without drive 
(obviously class-A) and you do not want to key them long-term in Tx 
or you risk over heating them. They drive with 5mw.

Ed - KL7UW

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I believe my Harris analog TV PAs were in the 20 db gain region - apx 10
watts in for a kilowatt out. I believe the digital PAs were lower gain to
run as class A (or very close to class A).

 >From the analog exciter output to IPA to PA to low-pass/filterplexer output

it was from 250 mw to 30 kw. That would be over 50 db gain! And that system
was type accepted.

73
George - AI4VZ


73, Ed - KL7UW
   http://www.kl7uw.com
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