Hey guys I just bought a used Heathkit EUW-15 Power supply from ebay and I havent done made any changes in it. It has all the original caps and fuses that it came with along with the tubes.
Here is the schematic and specs. Attached below as well
https://docs.google.com/viewer?a=v&...DItNzkwZS00MDM0LTljZGUtZjk1M2YwZDUwY2Jm&hl=en
Now it has two selections a voltage divider and voltage regulator.
The first time I powered her on, I had it in the voltage regulator position and I used my Ohm/DC meter to measure the voltages it was putting out and it was working as I expected it to.
As I turned the regulator knob the voltage went from 150V to about 380V
Then I turned her off.
I turned her on again and the voltage regulator knob has stopped working, to my surprise it is putting out a constant 520V which is much higher than what it is rated for. The capacitors inside are only 350V so I shut it off to avoid damaging them.
No matter which direction I turned the voltage regulator knob, it was a constant 520V.
However whats interesting is that the voltage divider selection works just perfectly, it puts out about 480V at its highest setting which it is supposed to do based on the specs sheet.
I get different fractions of voltgages at every knob turn of the voltage divider potentiometer. As it should be.
So First I tested the potentiometer to see that it was not open, and had the proper resistance values and it is working just fine.
The schematic gives me voltages to measure and I am going to do that next however I am wondering if I should change the caps and fuses anyway?
And I am curious as to what could be causing the voltage regulator to be putting out 520V when its not designed to do so.
More interestingly the voltage regulator worked perfectly the first time as I turend the knob the voltage went from 150V to about 350V, and now has stopped working putting out constant 520V which leads me to believe it could be a bad capacitor. Now the turning the knob makes no difference which is very strange it keeps the voltage at a constant 520V.
I tested the voltage regulator output with no load but it is designed to work without any load present and still put out the same rated voltage.
Here is what it looks like:
http://cgi.ebay.com/ws/eBayISAPI.dl...witem=&sspagename=STRK:MEWNX:IT#ht_500wt_1145
It has pictures of the insides as well
Attached as well, sorry guys im new dont know protocols yet
Here is the schematic and specs. Attached below as well
https://docs.google.com/viewer?a=v&...DItNzkwZS00MDM0LTljZGUtZjk1M2YwZDUwY2Jm&hl=en
Now it has two selections a voltage divider and voltage regulator.
The first time I powered her on, I had it in the voltage regulator position and I used my Ohm/DC meter to measure the voltages it was putting out and it was working as I expected it to.
As I turned the regulator knob the voltage went from 150V to about 380V
Then I turned her off.
I turned her on again and the voltage regulator knob has stopped working, to my surprise it is putting out a constant 520V which is much higher than what it is rated for. The capacitors inside are only 350V so I shut it off to avoid damaging them.
No matter which direction I turned the voltage regulator knob, it was a constant 520V.
However whats interesting is that the voltage divider selection works just perfectly, it puts out about 480V at its highest setting which it is supposed to do based on the specs sheet.
I get different fractions of voltgages at every knob turn of the voltage divider potentiometer. As it should be.
So First I tested the potentiometer to see that it was not open, and had the proper resistance values and it is working just fine.
The schematic gives me voltages to measure and I am going to do that next however I am wondering if I should change the caps and fuses anyway?
And I am curious as to what could be causing the voltage regulator to be putting out 520V when its not designed to do so.
More interestingly the voltage regulator worked perfectly the first time as I turend the knob the voltage went from 150V to about 350V, and now has stopped working putting out constant 520V which leads me to believe it could be a bad capacitor. Now the turning the knob makes no difference which is very strange it keeps the voltage at a constant 520V.
I tested the voltage regulator output with no load but it is designed to work without any load present and still put out the same rated voltage.
Here is what it looks like:
http://cgi.ebay.com/ws/eBayISAPI.dl...witem=&sspagename=STRK:MEWNX:IT#ht_500wt_1145
It has pictures of the insides as well
Attached as well, sorry guys im new dont know protocols yet
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