1) Dan's Kits and Parts is a good source. There's also a hamfest vendor in my area who brings a lot of them to the various venues. I'll have a look next time and get contact info.
2) What taper (linear, audio, log, reverse log), single or multiple gang, shaft diameter? Details, man!
Linear would be best. Don't care about anything else.
I need to attenuate a noise sensing antenna in certain situations. Will help achieve better phase cancellation of local noise sources.
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So there I was, totally naked. With only a rubber hose and a stuffed animal...