Vintage Synth Repair

Thanks to those who offered their advise on the display.


Someone mentioned replacing a cap.  I do have some soldering on board experience so I was wondering what cap needs replacing...Where is it located and what value should I get (and where?).  Does anyone have a service manual they can scan the page that shows where the cap is located that they can email it to me?


Also, the "Low Battery" message appears on start-up so I was wondering what battery is needed?  I'm hoping to be able to get the battery first then take the unit apart, replace the battery, locate the cap and see what's involved in the repair.  I'd prefer to have the battery beforehand so I can simply remove the cover and put in the new battery then zip it up instead of having it laying around apart while I try to locate a battery for it.  If I know what cap to get and get it in advance, I could do that too at the same time.


Thanks in advance.


Greg

I worked on an XP50 a few months ago and had similar kinds of problems, 
the display didn't work and the likelihood was a problem with the 
contrast control system. The bad news was that a lot of the SMD 
electrolytic capacitors on the main board were leaking, failing and 
leaking a corrosive liquid over nearby components, There is a dual 
op-amp which handles both contrast control and battery monitoring and 
all the electrolytics nearby were leaking, I replaced all the SMD 
electrolytics on the main board (there were 27 if I recall) and two 
thirds of those removed were faulty according to a capacitance and ESR 
tester. Alas on this particular machine, the ASIC which drives the 
display was faulty and is unobtanium so this one bit the dust. I had 
just bought a new display and a keyboard key for it so I lost out 
heavily on that one. Forum gossip seems to hint that all the XP series 
suffer from capacitor problems.


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