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[AMPS] Follow Up on the SB-220 Follow UP

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Subject: [AMPS] Follow Up on the SB-220 Follow UP
From: wfairclo@netcom.ca (Walter Fairclough)
Date: Thu, 18 Mar 1999 23:17:06 -0500
Further testing indicates only the 0.82 ohm resistor blew. I replaced it
with Harbach supplied 0.82 3W WW. Turned amp on, everything appears normal
unkeyed. Keyed, the resting plate current now reads 160ma, down from 210ma
before bang. Don't know why. I could try shorting out another bias diode to
bring it up to 200-230ma or is 160ma OK. This would make 2 diodes shorted
out of the existing 8.

Suppressor resistors measure 30 ohms on both tube anodes. Don't know what
they were before but 30 ohms seem reasonable.

Will apply drive tomorrow and see what happens. If the lights dim on the
continent, you'll know why.

Walter - VE3EN



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