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[TenTec] Misc. amp/qrp comments

To: <tentec@contesting.com>
Subject: [TenTec] Misc. amp/qrp comments
From: k5uj@hotmail.com (Rob Atkinson, K5UJ)
Date: Mon Jun 2 13:30:12 2003
First, new eham review of the Titan III: 
http://www.eham.net/reviews/detail/3152

Re the comment that screen driven amps (such as the Titan III using 4cx800s) 
require relatively small drive power (so higher exciter power not needed) 
I'd like to make the point that cathode driven gg amps while requiring 
higher drive, are generally thought to produce cleaner output.

Re the comments to the effect that qrp/exciter power is somehow enough; <= 
600 w. is enough; a huge increase gives you only 1 s unit higher sig. 
strenghth etc., these assertions usually assume(1) or ignore (2):

1.  qrp/exciter--one or more of--a lot of free time and patience; mostly cw 
and maybe a hot band; pretty good antennas.  If you have antenna 
restrictions, not much operating time and want to spend it in a qso, want to 
operate phone and with armchair copy, then you are probably going to need 
more than 100w.  Especially below 17m. in summer.

2.  watts per S unit:  after you have put up the best antenna you can get 
away with (and afford) the amp police will somehow try to make it seem like 
you have to justify getting a 1.5 kw amp.  One way is to argue that x no. of 
watts will only give you a tiny increase in signal strength.  This is one of 
those cases where the math is right but ignores a few things such as:  Noise 
level (both QRN and the competition in a pileup) and the human condition.  
The human condition is that the guy at the other end will want to talk to 
you or pick your call out in a pileup if you are loud.   Who doesn't want to 
spend time making contacts and having ragchews?  I guess it's op. preference 
but my idea of a good time is not tuning around, reading the mail and 
struggling to either copy or be heard.  A 1.2 kw amp will ragchew 
effortlessly at 600 w.

73,

Rob Atkinson
K5UJ
k5uj@hotmail.com

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