1984 countertop Sanyo Microwave - diode + capacitor ?

[vap0rtranz]

Model Number

EM-2520KS

Age

More than 10 years

Hi,

Are there high voltage capacitors with diode built-in?

I opened up my 1984 countertop Sanyo after it stopped working and expected to find a bad fuse or bad diode. I found a good fuse and ... no external diode anywhere. (I did find dead mouse corpse inside the cabinet while tracing circuits, hah!)

Attached is the wiring schematic and picture of the capacitor. It appears the the diode is inside the capacitor's circuit?!

Could I just add a standard in-line diode to the hot terminal of the capacitor? Or do I have to replace the whole capacitor?

Here is an eBay listing of the same rated capacitor as comparison: https://www.ebay.com/itm/334835476575.

The microwaves symptom is everything still powers on but it generates no heat and makes a louder humming sound when microwaving than it normally did.

And yes I did short out the high voltage capacitor terminals with an insulated handle screwdriver. Actually did that a few times because I'm paranoid.

 

[Dan O.]

It appears the the diode is inside the capacitor's circuit?!

That appears to be the case although I've never encountered one before and we even did Sanyo factory service!

Could I just add a standard in-line diode to the hot terminal of the capacitor? Or do I have to replace the whole capacitor?

A separate diode could be used with a separate capacitor. I don't know that I'd risk reusing a known defective part ie. the capacitor. Who knows if it will fail in other ways later. It is in a high voltage circuit and could possibly present a safety hazard should it fail further.

JMO

Dan O.

 

[vap0rtranz]

OK, so replacing the capacitor entirely sounds like the best plan of action.

Thx Dan.

 

[Dan O.]

so replacing the capacitor entirely sounds like the best plan of action.

That would be how I'd proceed, especially if you can get an exact replacement.

Dan O.