Minolta Di520 copier problems - power supply PU1

Jan 29, 2009 2 Replies

I am trying to fix a 1999 copier that was running when I picked it up, but shortly afterwards came up with two different error messages - the first was C-11EE (PWB-B) and now it shows C-0020 which (according to the service manual) means a problem with motor M21. Checking motor M21 shows a lack of 24VDC, and tracing back to the master switching power supplies I find one section that is missing the required 24VDC, but it does have the correct input voltage.



Unfortunately I do not have schematics for the switching supply (PU1) and so am down to eyeballing the sucker and making a stab at finding the problem. First suspect (of course) are the capacitors and we will be using Bob Parkers' great ESR meter on those, however I am trying to find as much info on the machine as I can so if anyone has the schematics for the switching supply I would appreciate a copy.



Now the machine also has another problem - caused by me (sigh) - where I accidentally damaged the Timekeeper RAM IC (trying to back it up with the wrong programmer because I assumed that the 11EE error meant the Timekeeper battery was failing (almost ten years old!)) and now the machine only shows Japanese as I blew away the English text. If anyone can read the Timekeeper IC (SGS: M48T35Y-70PC), it is apparently the same as a Dallas DS1644, I would also appreciate that!



Lastly I need a replacement spring hinge lid for the duplexer/scanner lid as the bushing has blown out...



I am located in Vancouver, BC, Canada.



Thanks!



John :-#)# PS - I do have a PDF copy of the manuals for the Di520/620 that I can share - I just wish they had the PU1 schematics!


(Please post followups or tech inquiries to the newsgroup) John\'s Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 Call (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

I would look for a connector problem or wiring break in the moving, copier electronics is very reliable. Otherwise too much of a coincidence. Some control signal that is disabling part of the ps perhaps? one of those flimsey paper path microswitches or lens/mirror assembly traverse limit switches getting mispositioned/dislodged could be another such a cause

-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on

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Yes, those were indeed my first suspects, however as far as I can tell I have eliminated them by re-seating all connectors, after examining their pins for wear, and the problem does appear to be electrical.

Thanks,

John :-#)#

(Please post followups or tech inquiries to the newsgroup) John\'s Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 Call (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out."

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