conductive plate for theremax? what the..?

Hi guys,

I'm so confused about this conductive plate business. If I put a big sheet of tin (foil) underneath my theremax, won't that just short circuit all the components?

Also, it says that the power cord box was supposed to have instructions on whether the striped end was positive or negative. Well, no such luck... any suggestions how I can figure out which end is positive or negative? the only thing I know is that it shows -o+ ono the transformer itself.

Thanks!

No it won't if you are mounting the PCB on standoffs as described in the manual.

You can easily detemine the polarity of the wires coming off of the power supply using a voltmeter or DMM. Plug in the power supply (wall wart) and check the wires with the meter. If you get a negative reading, switch the leads. When you get a positive reading, the red lead of the meter is positive and the black lead would be negative.

Personally, I don't understand why they are telling you to hardwire the power supply in the first place. I would purchase the mating jack and install that in the theremin, so the power supply can be removed. Or am I missing something?

Ok, thanks for the help! I didn't buy the case kit, just the faceplate and electronics, so the standoffs weren't included (I got a bit confused about that!).

Good idea about the mating jack thing, I'll see if I can find something at radio shack.

If you can't find any ready made standoffs at Radio Shack, here are some other possible options.

There's a remote chance Lowe's or Home Depot might carry them in their "specialty" hardware drawers.
Otherwise, you could purchase a short length of 1/4 inch nylon tubing.
Or, if you have some old ball-point pens laying around (with a straight tube, such as a Bic, etc.) you can cannibalize one of them.
I've even seen pieces of a plastic straw used, but they aren't very sturdy.
Another option is to buy a small wooden dowel, cut it into short pieces and carefully drill a hole through the center.

cool, thanks! maybe some of the ones I have in my PC parts box might work... otherwise RS is a good choice.