Michael,

I owned a modified SB220, which means it was running on 220 volts, that's a 
given, had a beefed up power supply, and several other modification.  Even 
with well used tubes, I got about the same results.  In CW mode, I got about 
1200 out on 20 meters when really pushing it.

Phil.
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----- Original Message ----- 
From: "Michael Ryan" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, August 14, 2009 1:21 PM
Subject: Heathkit SB-220 HF Amp output


> Hi all:
>
> I recently picked up a Heathkit SB-220. After taken the steps
> necessary to bring it up slowly, the amp was idal for 15 years, here
> is my results.
> I use an LDG Electronics TW-1 Watt Meter to tune and here are the steps.
> 1. Placing the meter in tone mode, key down in CW, Adjusting the Tune
> control on the amp to find the highest pitch possible. That's how you
> find the plate setting.
> 2. Key down in CW, with tone mode, adjusting the load control to find
> the highest pitch possible. With 10 watts from my exciter, I see about
> 180W.
> 3. With the amp in stand by, I increase my exciter to 100, re_ingage
> the Amp in CW, adjusting the load control for yet more pitch.
> The result is approximately 1000W. Note the amp is in CW/Tune and each
> adjustment on the controls take about 10 seconds.
> When I reduce my exciter's drive to 60W, I see 800W with the amp still
> in CW/Tune. When I switch the amp to SSB, I only get another 200W.
> Total output, 1KW on SSB with 60w of exciter drive. With 100W drive, I
> won't see no more than 1300.
> Is this normal? I don't think the tubes are bad because the amp powers
> up to spec in CW/Tune.
> 100W drive =1000.
>
> TNX all & 73:
>
> Michael De VO1RYN
>