Found this little home brew box in a pile of stuff. I understand the BNC to binding post adapter, and the hot to ground reversal switch. I don't understand the 330K resistor... anyone venture a guess as to what the builder intended here ??

I suppose maybe a high to low impedance converter (or the reverse) of sorts... but as crude as this implementation of such a device as this one is ... what was it supposed to be used for ?

It's the sort of thing you might use with a sensitive galvo or other detector to eliminate polarity errors, but there's never a way to short out the 330k for full sensitivity. Something audio for getting minimum hum, but again, the 330k seems high.

With no context and no labels, it is an inscrutable mystery. What other sorts of things were associated with it in the group, if anything?

No telling if the binding posts were the output or the input, likewise the BNC. And the unused binding post was grounded.

It's also possible that the builder was trying out an idea that turned out not to work.

I've got some of those too.....

[quote]What other sorts of things were associated with it in the group, if anything?/quote]

It was in an auction flat with "other things" I'm afraid it's true purpose shall be forever lost to history. I may just remove the resistor and use it as a BNC to banana converter. It's in a nice little shielded box about 1"x1/2"x1/2"

An input adapter, where the coax (signal) is in/out to an instrument/radio or RF source is parallel.

I made such a device for a Hammarlund SP-110x radio to "flip" the antenna which was coax to either side of the two terminal antenna input for the radio. The antenna was only partially resonant so the shield of the coax was ,on certain bands, picking up signal. I would not know the signal was there unless I flipped the switch. My circuit was deLux I also included a ground selector switch. Crazy? No, it worked and it is still attached to the radio via the terminal screws, I don't like permanent mods to a boatanchor. It was my first experiment with printed circuit. I had a pal that worked at the local printed circuit factory, I got scrap board and some etchant. Mil spec fiber glass, tough as nails board too...

Chas

We locally manufactured some stuff like that at work. Without any labels or context they would be a total mystery to anyone and so specialized that even if you knew you could not use it for much else. They are for parts, or what you can make of them.

It appears to be an early component from a Turbo Encabulator

My best guess about the resistor... It prevents a short in case the switch makes contact between 1 and 2 when switching position.
I would check for a short between 1 and 2 when switching before removing the resistor.
Why 330k? No idea.

That's a relief. I was thinking it might have been a DiLithium Crystal Degenerator .........

Personally I think that it's the input network for a Heisenberg compensater.

For testing a stereo amp. Feed signal to left input with right channel input grounded.

Then the other way.