Gun Fight big cap popped

Mr Do

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Looking for identification and where to get this cap??--.01 MFD and 1600 VDC???
It is on a B&W Midway chassis 161-900.
Any one seen this?
Any help welcome.
Did this pop from old age?
 

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Is it a POLYPROPYLENE or Mylar or ceramic? How is it identified on the electronic websites?
 
Chad will be able to tell you he just put new ones on mine ninepins check it but it's still in transit.
 
It's a paper cap. They do that sometimes...

Replace it. Mouser should have a suitable replacement. Any kind of poly film cap will make a good replacement. 1600v caps aren't super common, but the big suppliers stock them.

-Ian
 
MFD is uFD

Are we sure MFD is uFD? the 1600 VDC didn't freak me out on a monitor, the .01 uFD made me do a double take.

New ones are so tiny, just 35 years of progress?
 
Are we sure MFD is uFD?
Positive. MFD is an old abbreviation for microfarad, before they started using the "micro" symbol, which is the greek letter mu (µ). I would assume it has something to do with making abbreviations out of standard characters available to conventional printing technology. Most stuff since the 80's has been marked as µF, however.

the 1600 VDC didn't freak me out on a monitor, the .01 uFD made me do a double take.

It's not an electrolytic capacitor. .01 is a very common value. You just don't normally have to replace non-electrolytics, because modern ones don't age or fail often.

New ones are so tiny, just 35 years of progress?

Yup! Modern caps are made of polyester film, or some other stable dielectric. Old ones were made of wax paper and aluminum foil, and sealed with wax or glue. They don't age well. Paper caps lived on into the 70's and 80's on occasion for high voltage applications, before they got the materials and methods really down. But back into the 50's and 60's, all capacitors were made like that. Very common if you work on any vacuum tube type equipment. Recapping is mandatory there too, but you're replacing all these paper caps as well as the handful of electrolytics in the power supply.

-Ian
 
Paper and Foil

Yep, got a nice shot of the oil paper and foil
page117-1002-full.jpg


in the interest of full documentation I started a page for this blow out: http://arcade.melchman.net/pr0n/midway161900/index.html
I will update it with more and better picture when I rip it down to replace the cap.
 
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New problem

So we replaced the blown capacitor, reassembled and powered up. Now a resistor on the Power Supply board (161-901-1) smoldered and burned.

Ok, not problem I have a pile of resistors, looking at the schematics I will just find it, get the K reading and replace it It is labelled 100ohm, no K does that man 0.1 K?

ANd then I need to figure out why it is getting too much voltage that it can't resist!
 

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It is labelled 100ohm, no K does that man 0.1 K?
Correct. But do mind the wattage. You need a resistor the same or greater wattage than the one you're replacing.


ANd then I need to figure out why it is getting too much voltage that it can't resist!
Usually resistors burn up because too much current is being drawn through them. Look for a shorted transistor or something.

-Ian
 
GF

quote:
Usually resistors burn up because too much current is being drawn through them. Look for a shorted transistor or something.

Could be that 1000uf 100v cap with a leak:)


Ian keep reading this thread. Your very helpful! Thanks.
 
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