I tried repairing mine with no success, as an alternative I did this. I pulled 2 small speakers from dell computer speakers, ran 4uf caps across the terminals and wired them in series to the main speaker- sounds great and no more electrostatic nonsense to deal with.

I tried repairing a couple once with limited success.

If one follows the repair article exactly as written the electrostatic tweeters should work again in almost all cases.

Rich:
Did you see my above post on previous page?
How would you proceed. Pull the chassis and check resistors/change relevant caps?

Thank-you.

It may sound decent that way, but will sound nowhere as good as it would have with the electrostatic speakers still working.

Hi Danny,
My next move would be to disconnect all tweeters and (with radio OFF) measure the resistance between the the two wires that connect to each tweeter. Do you get 2 ohms across each pair? I will guess that you will, but we should do this check anyway before jumping ahead.

I looked at the schematic again. I believe the combination of part failures required to result in 2 ohm resistance across those wires is unlikely, although anything is possible. I suspect a miswire is more likely. There are only 4 parts specifically for the tweeters, a 5nf (.005uf) cap connected to the EL84's plate on pin 7, a 5k ohm resistor from the other side of that cap to circuit ground, a 10nf (.01uf) cap from the 5nf-5k junction to the positive tweeter lugs (this is how audio gets to the tweeters), and a 100k ohm resistor that puts a high DC voltage charge onto the tweeters (which is required for their operation). The 100k ohm resistor connects from the EL84's screen grid (pin 9) to the junction of that 10nf cap and the tweeters positive lugs. The tweeter's negative lugs should connect to circuit ground. In order for there to be a very low resistance across the tweeters wires, the 10nf cap would have to be shorted AND the 5k ohm resistor would have to be shorted, or some other tragic combination of failures that would probably affect the radio's audio output. Although capacitors can and do short circuit, it is very unusual for a resistor to short circuit, they almost always rise in value unless there is a reason for catastrophic failure like burn up. So, I am skeptical that part failures are the cause of this.

Please report whether or not there is a near-short circuit (2 ohms) across those tweeter wires. If there is a short, I suspect a mis-wire, perhaps someone has been in there and done something dumb.

Sorry I cannot log into the forum very often, I'll try to stay involved on this as much as I can though.

I agree with Tube Radio that the original tweeters will sound great once repaired (or replaced). My EMUD Rekord sounds very sweet with it's repaired tweeter. I don't agree with Tube Radio to replace all paper caps yet. They are old and probably leaky and could stand to be replaced, and will only get worse over time, but I don't think that explains the symptoms here.

It may not solve the problem, but would eliminate the possibility of a capacitor shorting and taking out other components with it if the op continues to have the radio powered up while troubleshooting the tweeter circuit.

Before I so something stupid, would I do any harm if I connected my "working" tweeters, which are the exact same as the tweeters in the radio, to the external speaker connection on my EMUD T-7 ? The connection calls for a speaker of about 5 ohms.

Thank-you all.

That wouldn't work at all as the tweeters require a dc voltage and also a much higher audio signal level.

No tweeter sound would emit but no harm would be done.

It would be helpful if you can answer my question from before...with all tweeters disconnected what resistance do you measure between the wires?

Thanks Rich and Tube Radio.

Rich, check for PM.

Hello:
I asked the ebay seller of my "tested and working well" replacement electrostatic speakers what kind of radio he actually heard them working on. He answered MARANTZ 2240. Here is one: http://www.classic-audio.com/marantz/2240.html
Would this radio create the proper dc voltage and audio signal level for these electrostatic speakers?

Thank-you.

I do believe thine ebay seller hath smitten himself. There is not a snowball's chance of 200vDC coming out of that receiver!

To give the seller benefit of doubt, I suppose it is possible that, presuming those tweeters are good and the seller did hook them up, and if he cranked the receiver's volume all the way to 11 with a tweeter next to his ear like a headphone, he may have heard some faint whispers. Maybe.

Thanks Rich.