[AMPS] your sb-220 mod

[Steve Harrison]

At 09:02 AM 2000-01-19 -0500, Pete Smith wrote:
>
>At 11:09 PM 1/17/2000 -0800, Skipp wrote:
>>
>>Sounds more like your meter is telling the wrong story...
>>More formal test equipment might be in order.
>
>Could be, but I don't have access to anything better.  It does seem odd
>that this is happening on only one band, in the middle of the operating
>frequency range, if that's the reason.

You've mentioned that you've bypassed the new input relay; but how about
the new output relay? Bypass that, then bypass the new input relay, too, if
the problem persists.

>Any comments on another hypothesis?  I want to check the operating bias
>voltage, because it occurs to me that I could have RFI affecting the
>electronic bias switch, such that I'm actually biasing the amp into a
>different operating mode with higher efficiency.

Entirely possible but any external metering that you hang on the circuits
will likely disturb things in some way. But in fact, this sounds like a
likely possibility.

73, Steve K0XP

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