[AMPS] Alpha 77DX Bias Switching

marv h. gonsior w6frmarv@juno.com
Thu, 13 Mar 1997 12:34:18 PST

Hello ampers,

Has anyone had any experience with the problem of excessive Electronic
Bias Switching speed in the 77 amplifiers, causing distortion and the
recognizable "crackling" sound that results?

>From my experience with a home brew EBS, an integrating circuit across
the switch eliminated the problem and yet it was fast enough for QSK. 
My supposition is that ETO felt the high-speed switching was necessary
for QSK operation but the results, in some that I've heard, are rather
poor.  In one amplifier test, with the EBS shorted out, the quality was

Are there any mods for the apparent problem?


Marv, W6FR

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