Boy I hope you don?t need a flak jacket.
However, I see you must have been reading for a while!
I would agree that class C for CW mode is more efficient, that subject just
doesn?t come up anymore.
As a fun study, NCJ this month just published the 1998 November Sweepstakes
results by year of check (the first year of license for the operator). It is
interesting in that older licensees are more heavily weighted towards CW
operating and those first licensed later (especially 90?s) much more entries
and scores for phone. It?s been a while since I?ve heard of anyone
considering a CW only amp.
More power to ya! (pun intended)
The advantages of a 3CX1200 series relative to the 8877 basically are:
Instant on
Rugged grid (50 watts)
No grid protection needed
No worries about limiting drive for excessive grid current.
Biggest advantage of 8877 to the 3CX1200 series:
Less drive required for legal limit output. Approximately 50 watts = 1500
watts out(many factors influence this, just for comparison), where the
3CX1200 series takes about 75 watts = 1500 watts out.
More 8877 available used as pulls
Count on the anal ones to pick apart my above statements, but sometimes it
just goes too far when we need to define what the definition of IS is all
the time.
Also, don?t listen to the blather about parasitics everywhere, too many
success stories prove otherwise.
73, Dan Magro W7RF, (President WARC 1999, member SCDXC, SCCC)
Manufacturers Rep & Distributor for HENRY RF Power Amplifiers.
RF Applications Power Measuring equipment, See the VFD!
www.radiodan.com <http://www.radiodan.com> RFpower@radiodan.com
<mailto:RFpower@radiodan.com> A trip to our web site is worth the click!
> -----Original Message-----
> From: owner-amps@contesting.com [mailto:owner-amps@contesting.com]On
> Behalf Of Chip Owens
> Sent: Tuesday, September 28, 1999 12:41 PM
> To: amps@contesting.com
> Subject: [AMPS] Amplifier for cw only-question.
>
>
>
> If one uses an hf power amplifier for cw operation only is there any
> good reason to operate it in AB1, AB2, or class B? Wouldn't class C
> operation yield higher efficiency and actually make QSK operation
> easier to implement?
>
> Also, I'm curious if anyone out there is using the 3CX1200Z7/YU-181 in
> a homebrew amplifier. With its grid terminal brought out to a large
> circular flange on the tube base it would make an essentially zero
> impedance grid-to-ground connection. The data sheet mentions use of the
> SK-410 socket, but no chimney is mentioned. Is this series of tubes,the
> 3CX1200A7, 3CX1200D7, and 3CX1200Z7 a good choice for a homebrew amp
> over something like an 8877?
>
> This is my first posting to the reflector. Do I need to put on my
> flak-jacket before reading replies?
>
> Chip, NW0O
>
> --
> Chip Owens (owens@atd.ucar.edu)
>
> --
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