For those building kits or homebrew projects that notice wiggling of wires
produces static, a number of things could cause this.
1) To protect the copper side of your new project from shorts, make sure to
lay it down on an insulating material like a sheet of a page protector, mylar,
glass or something that is a good insulator and cannot be pierced by snipped
off component leads that get overlooked on the bench. Or bits of bare wire,
or even metal small tools left out. It they don't short something, they could
momentarily touch something and make static heard.
2) Direct conversion receivers, which the 38S is not, have high audio gain,
and might be found to amplify triboelectric effects which is the movement of a
conductor in an electromagnetic field, and this could be a source of static.
Perhaps the 38S has enough audio gain to do this as well? I have not looked
at what the overall gain budget is yet, (mine is still in the envelope), but
perhaps this is a cause. I think 60 db of gain will make such effects
noticeable, and that is not a lot of gain these days of good op amps, etc.
3) Perhaps this should have been number one: If you have static, make sure
of your SOLDERING quality. Shiny, proper flow around each wire, etc. The
overwhelming cause of troubles is bad solder joints. Use a magnifying glass,
or work under one of those 3X illuminated desk lamps, and inspect every solder
joint after it is made. Inspect all again before first applying power.
Inspect immediately if something does not measure correctly in check out, or
the rig seems deaf or dead given an antenna or test signal. Inspect---I think
you get my drift.
Good luck, may all your solder joints be shiny ones!
Stuart K5KVH < rohre@arlut.utexas.edu >
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