>
>Recently I modified my SB-220 to incorporate vacuum-relay QSK. In the
>process I did very little to change the RF cabling under the chassis, but
>the input side relay did require a total of 3 inches of small diameter coax
>to connect to the existing cabling.
>
>To my surprise, these physically small changes have had a relatively
>significant effect on input SWR, particularly on 40M, where the input SWR
>now indicates close to 2:1 on my TS-930. The TS-930 doesn't mind, but a
>(probably) related phenomenon concerns me. On 40m, when I have adjusted
>both the tune and load caps for maximum output at about 110 watts of drive,
>the plate current is indicating ~ 850 ma. key down, where previously it
>indicated about 750 ma. with identical driving power and antenna.
>
>Any idea why this is happening, and should I be concerned?
Did you put the high speed relays and the electronic cathode bias switch
on the same piece of perfboard?
- Rich..., 805.386.3734, www.vcnet.com/measures.
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