[AMPS] SB-220 High input SWR and transceiver fold back

[Phil Clements]

> I have been having a problem with my FT-847 transceiver output power being
> folded back when driving a SB-220 in SSB mode due to erratic SB-220 input
> SWR.  The input SWR of the amplifier is varying between 1:1 and 5:1.  As the
> SWR increases, the power of the transceiver reduces due to the automatic
> fold back circuits and therefore amplifier output power reduces accordingly.
> If the transceiver is set to CW then SWR is 1.2:1 and amplifier produces
> full output.
>
> My previous TS-830S exciter always produced correct output ... but it didn't
> have any fold back circuits either.
>
> Is this a normal situation using solid state exciters?

Is this happening on all bands?
If only one band, you have probably toasted the mica caps on the input Pi
matching network. I have also seen an input coil melt down in some cases.
Further info needed to make more suggestions.

GL!
Phil, K5PC




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