Got an Etherwave Plus for free, it's not turning on

Hi there, pleased to meet you! Such a no-fluff forum - great stuff. 

Anyway... the other day I got my hands on a secondhand Etherwave Plus for free, through a friend. It came with a power supply in 2 parts: 

1) a standard Moog Music wall wart power supply with the special connector
2) an adaptor for UK plug sockets.

After plugging in the Etherwave via the 3-pin the other day, it powered on fine, with the red 'PWR' light turning on. 

However, after trying again today, it seems like the theremin is no longer receiving power. The light now doesn't turn on after being plugged into the outlet, and I'm fairly certain I haven't bashed the theremin in any way that would hurt it.

Assuming trying all the different outlets in my house won't work, how would I best go about diagnosing this problem? I've not got a super technical mind so I don't currently know anything about multimeters or voltages and how they relate to supplying power to theremins, but I'd be willing to learn if I knew the next best course of action - if anyone is willing to divulge?

Thanks in advance!

iltli, can you get your hands on a multimeter?  They're not expensive anymore.  I'd test the UK adapter first (which I assume cuts the AC voltage in half?).

Hey Dewster, thanks for the info. Got my hands on a multimeter this morning - need to do a bit of research on how to test the UK adapter's voltage with it, will report back here today.

Hello again! So I tested the voltage of the UK adapter. I'm getting 245 V out of it, which is (just about) the average from a UK outlet. 

So contrary to your suggestion, it doesn't seem like it's halving the AC output!

I guess the next step would be to test the Moog wart itself from its DIN connector, but I can't find anything online on how to hook the multimeter up to it. Any guidance on that front?

Hello again! So I tested the voltage of the UK adapter. I'm getting 245 V out of it, which is (just about) the average from a UK outlet.  - iltli

That seems kinda like a bad situation?

"I guess the next step would be to test the Moog wart itself from its DIN connector, but I can't find anything online on how to hook the multimeter up to it. Any guidance on that front?"

On the DIN connector, pin 1 should be 14VAC, pins 2 and 3 are ground.

I don't see schematics here at TW for the EW+ right off, but here's an older EW / Big Briar one that might help: https://www.mikrocontroller.net/attachment/310842/etherwave.gif

If the transformer output is good I'd next check for +12VDC and -12VDC at the regulators.

Thanks for all this guidance dewster, sure to prove very useful - I'll test it once again this evening.

As for this...

That seems kinda like a bad situation?

How come?

"How come?"  -iltli

Doubling the voltage into the transformer could be catastrophic, those regulators can only handle so much in the way of input voltage (not to mention the diodes and electrolytic filter capacitors) it wouldn't surprise me if one or both are fried.

Doubling the voltage into the transformer could be catastrophic, those regulators can only handle so much in the way of input voltage (not to mention the diodes and electrolytic filter capacitors) it wouldn't surprise me if one or both are fried.

Thanks for the info, but I'm not sure that's what's happened.

I just probed the DIN connector: through the UK adaptor and the wart, it gives an output of 7 V.

Weird, that seems to be half what the theremin needs (14 V), no?

Edit: given what you've said already, could that halving mean the transformer is fried?

"I just probed the DIN connector: through the UK adaptor and the wart, it gives an output of 7 V."  - iltli

I honestly don't know what's going on there.  The wall wart is AC, if that helps, which is a little unusual.  What does the down converter look like and is there any way to test that with a different piece of 120V equipment or another appliance?

OK, correction: I now realise the theremin needs an input of 120V, not 14V as I thought earlier (silly me)

also going to mimic your quoting style as it's much better than the default

I honestly don't know what's going on there.

What exactly should be going on? If all was well and good, would my multimeter be giving a reading of 120V when probing the DIN?

What does the down converter look like and is there any way to test that with a different piece of 120V equipment or another appliance?

Unfortunately no, I don't own any other appliances of that sort
And apologies for my lack of terminological breadth... I assume by down converter you mean the entire Moog transformer? Here are a few pics: