View Single Post
  #2   Report Post  
Posted to sci.electronics.repair
John Robertson John Robertson is offline
external usenet poster
 
Posts: 907
Default The Kikusui COS5060A is down :-(

On 2017/12/11 5:14 PM, bitrex wrote:

Failed in the middle of a measurement last night - no display, no power
LED, a few red LEDs on the front panel come on intermittently at
power-up. The familiar burnt smell coming from the back, but no smoke.
The enclosure felt a a bit hotter than usual immediately afterwards.

The incandescents on the graticule working fine though, and they're fed
off the negative PSU rail, but the positive low-voltage supply is
definitely down for the count. I haven't had a chance to open it up yet
but hoping it's an easy fix...


My Tek scopes don't seem to have that 'smoke' option...

I've seen more bad caps than anything else take out equipment - bring
out the ESR meter and do a good run through.

A very nice looking, West German made 220/16 cap in our German Wurlitzer
jukeboxes seem to like shorting out (5VDC bus). Mind you it is on the
/Reset for the CPU, but I'm running into a lot of these axials that are
just turning in zero ohm resistors (zealous?).

Likely something like that happened in your toy too. Tantalums love
shorting out for no real reason.

John ;-#)#

--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd.
MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
(604)872-5757 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."