[Heathkit] SB-230

[Cam and Juli Hedrick]

I just opened up my modified SB-230 today to swap out the 572B's...the old
ones were Chinese.  The guy that did the mod on it new what he was doing. It
is a clean Collins styles solder joint amp.  I picked it up at a swapfest
not working recently and just opened it up today.  If any one what photo's I
can open it up again and shoot some to e-mail out.  To put the 572B's in the
amp he (or she) added a box on the back of the amp beyond where the
beryllium would be.  The original HV cover is used along with a slotted
cover on the extension and a nice whisper fan to draw air by the tubes for
cooling.  It appears to have parts like an SB-200 used for the
conversion...I have no idea why it was done if the parts were from a 200.  
Anyway, I just thought you might find it interesting.
The amp I did the 572B conversion on, I made anything I couldn't buy, and
get the same output. My design differs only in that I channel air over the
tubes for cooling...not really necessary with 572B's.
73,
Cam
WA4JKW