Subject: Re: Tech-MPU-35 Help please... Date: Sat, 08 Jul 2000 15:06:33 GMT From: edburtn@qson.net (EDLOCO) Organization: Altopia Corp. - Usenet Access - http://www.altopia.com Newsgroups: rec.games.pinball That Sucks, I know the feeling of moving Backwards. While I can't say what (if anything) was damaged on your MPU-35 Board, Here's some advice. If the The MPU is Locked up (no Flash) , Disconect J-4, THEN Check TP 1 on the Sol Dr Bd., This is the Regulated 5vdc That drives (among other things) the MPU. SOMETIMES, when the Q20 regulator goes bad, instead of 5vdc, it will send unreg +- 13..5 Volts to the MPU, thus blowing something there .If You fix the MPU, But Don't ck Voltages, then you Chance blowing out the new, working board.. Also ck out Other Reg Voltages such as the 230 Vdc. ...EL >>On Sat, 8 Jul 2000 09:02:55 -0400, "tat-2" wrote: >Hello, > >I have been working on an MPU-35, > >I took a known working board, swapped out the 6800, with a non-working(LED >on all the time) boards 6800. >It worked.(put unknown 6800 into good board).= 6800 good. > >Then I swapped out U11 from the known working board with the U11 (6821)PIA >from the NON-working (LED ON all the time). The working board locked up! >I then put back the known working U11...and now I have a pair of NON-WORKING >(LED on all the time boards). > >I tried and unknown, but new 6821 (u11) ( I bought it new from jameco). >It is still locked on. >Could someone please tell me what part or parts I damaged? > >tat-2 > > > I'M Serious about Women, Pinball Is Just For Fun ! Proud Owner Of: Better Pins than Cliffy NO Funhouse Ramp Repair Kits Indoor Plumbing Shoes Television (25in) Computing Machine NICKEL REJECTERS K MART Dishes (plastic) NO Canadian Nickels Gallon Jug of WD40 !! BIG Hammer !