What does it do with the plate voltage switch in the ssb position ??
If you get about 1200 to 13000 watts out on 20 or 40 with 100 watts drive
you are doing good...
73 and good luck
Jim W7RY
-----Original Message-----
From: Walter Fairclough <wfairclo@netcom.ca>
To: amps@contesting.com <amps@contesting.com>
To: <amps@contesting.com>
Date: Tuesday, December 29, 1998 5:17 PM
Subject: [AMPS] SB-220 Problems
>
>I've run out of ideas and could use some suggestions that may help to
rescue
>this SB-220 of mine.
>
>I had a catastrophic failure a while back due to Zener diode shorting that
>set off a chain reaction on other components. I have since replaced the
>meter/rectifier board with one from Harbach, did his parasitic mods and
>replaced the two
>3-500Z with new EIMACs. No matter what I do, the maximum power output that
>I can get in the CW position is about 700-800 watts (500 watts on 10m), and
>which is about 100 watts more than the old tubes. This is with 50-100 watts
>drive (depending on the band). This output is achieved with a plate
>current of about 350ma and a HV of 2100. Now if I do the math, something
is
>wrong. Also, I cannot seem to load to more than 350ma.
>
>I've checked the meter/rectifier board and all components read OK. Plenty
of
>grid and yes the input swr is 1:1 on all but 10m where I have to use the
>built-in antenna tuner on the exciter (FT-1000D).
>
>I suspect that with 700-800 watts out that is about all one can expect and
>that the plate current meter must have taken a hit and not reading
>correctly.
>
>Any suggestions or comments would be appreciated.
>
>Walter - VE3EN
>wfairclo@netcom.ca
>
>
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