Help - JansZen Z-600 - dead step-up transformer?

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hi all,

my friend and i now have all new capacitors, resistors and diodes in each speaker. nothing old except for the drivers and the power supply transformers.

well, same deal as before. one speaker sounds incredible and the other's electrostatic panels are faint sounding. we swapped the panels. the "faint' ones come alive in the other speaker. so, they are okay.

so, i guess that leaves the voltage step up transformer, right? we didn't check the voltage with a multimeter. were a little scared of getting knocked out with 1,100 volts ;-)

any advice would be greatly appreciated. this is a major bummer because the one working speaker, complete with AR2 woofer sounds downright incredible. it's just teasing me with the notion of having a stereo pair of these bad boys running on a diet of McIntosh MC60 tube power ;)

anybody got a spare power supply?

thanks,
Robby
 
This is simple enough.

You need to measure the good transformer - not the whole supply.

How to:

Remove the secondary wires going to the diodes - it's either 2 or 3 wires. Place a 12vac transformer's secondary on the primary of the good transformer. Measure the 12vac transformer's actual voltage when running and connected to the 120vac input of the "good transformer (GT)". That's where it would have been plugged into the wall, ok?

Now we measure the secondary votage of the GT!


[wall AC]--->[120v in - 12 vac out xfrmr](test voltage A)--->[Janzen GT in - seconday out] --->(test voltage B)


This tells us the voltage/turns ratio of the power transformer!

If you have used a transformer for this test that is 12vac or pretty close, you can just multiply the voltage you measured on the secondary of the GT by 10. Now you know the secondary voltage you need to replace the transformer!!

I'd order two and replace both. You only need something that is +/- 10-15% of the original values - the size of the thing is largely irrelevant as no current is drawn, so it can be considerably larger and somewhat smaller (usually) in core size.

It's likely something in the 250-500vac range depending on the number of diodes used in the mulitiplier stack, and the final bias voltage.

( ...you could always add another stage to the stack and use a lower voltage transformer, fwiw)

Which, brings us to the main question - did you change or check the caps and diodes in the voltage multiplier stack?? More likely than not you've got a shorted/leaky little ceramic cap there, and/or a dead diode.

Test the presumed bad transformer the same way. That will tell you if it is the xfrmr or the diode mulitiplier stack! :)

_-_-bear :Pawprint:
 
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