Lane - You are correct. The plate choke must be changed for 160 operation
per the article. But the input circuit can be used as I described and has
been FB for 18+ years.I meant that the original SB 200 plate choke doesn't
have any resonances on the WARC bands otherwise it would burn up. Alpha
374s can't operate on 12m because of plate choke resonance on that band.
73, Steve WB6RSE
>Steve,
>Be careful. I believe Doug used an old NRC R-175A plate choke. Check for
>resonances before applying the juice!! His original intent with this article
>and hence the selection of this specific choke was to convert the SB200 for
>use as a LOW BAND amp only, ie 160/80/40 meters.
>
>I just picked up a like new MFJ-259 swr analyzer and am anxious to do some
>fun stuff. This coupled with my faithful Heathkit HD1250 GDO should let me
>check most things.
>
>Last time I checked Derek K7FF had some of these R-175As in stock.
>
>GL and God Bless.
>
>Lane
>KM3G
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