Here are the results of my implementation of the 4CX400 in the144Mhz
conversion of the ) AM-6155.
1) 10 watts yields 500 (supplies set for 240V)
2) -44 volts bias yields 100 mA plate idling current
3) Observed efficiency: 65%
3) Bias voltage divider changes: R14 = 15K, R16= 4.7K
4) Paralell C2 with C1 on bias board. (These caps may need to be replaced
on many amps due to their age. I suspect bias instability may be due to
these caps failing in some cases.)
E-mail direct for more details -- John Lane, W8KX
--
FAQ on WWW: http://www.contesting.com/ampfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Sponsored by: Akorn Access, Inc. & N4VJ / K4AAA
|