Ford Peterson wrote:
>
> I bought an SB-1000 from an estate that looks to be unmodified in any way.
> Are there mods out there that I should investigate? Any on-line resources I
> should look at?
The stock plate RF choke may have a resonance near 17 meters. I replaced the
one in mine with an Ameritron AL80B choke, which works well on all bands,
including WARC. Cost about $25 from Ameritron.
There is a very high potential gradient at the fixed bandswitch contact that
grounds the 160-meter padder capacitor. This can actually cause a corona
discharge from sharp points on the contact and the wire connected to it. The
corona can lead to an arc, which can burn the contact. After you check that the
bandswitch contacts are all OK, remove the lead to this capacitor and place a
3/8" diameter brass washer over the end of the switch lug. Make sure the washer
is smooth and has no burrs. Solder the wire back in place, flowing solder over
the connection so that it is smooth.
Check that the carbon resistor in the parasitic suppressor hasn't overheated and
changed value.
A soft-start circuit will eliminate the crunch when turning it on, as well as
extend the life of the 3-500z filament.
73,
Vic, K2VCO
Fresno CA
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