>Hello, I have a lisa 2 that only tries to power up 1 out of 100 tries with >the switch.
If it turns on sometimes, it would seem the power supply might be ok. The Lisa power supply is turned on and off by the COPS421 on the I/O board. Clean the I/O board contacts and check the motherboard connector. If you have some test equipment, see if the COPS421 has power on pin 9 and the oscillator is running (pin 2 or 3, but the oscillator will be affected by a low impedance instrument); to do this, you will need to defeat the back panel interlock (eg. jam some cardboard into the switch on the back of the power supply.) Pin 14 of U7F on the I/O board should have about +5 volts with the power off; if so, try briefly touching pin 12 to pin 14; this should turn on the power supply. Good luck! James James MacPhail "Think not of engineering as art, [EMAIL PROTECTED] but of art as engineering" Sigma Seven Systems Ltd. [EMAIL PROTECTED] <http://SigmaSevenSystems.com> -- LisaList is sponsored by <http://lowendmac.com/> and... Shop buy.com and save. <http://lowendmac.com/ad/buy.com.html> Support Low End Mac <http://lowendmac.com/lists/support.html> LisaList info: <http://lowendmac.com/lists/lisa.html> Send list messages to: <mailto:[EMAIL PROTECTED]> To unsubscribe, email: <mailto:[EMAIL PROTECTED]> For digest mode, email: <mailto:[EMAIL PROTECTED]> Subscription questions: <mailto:[EMAIL PROTECTED]> Archive: <http://www.mail-archive.com/lisalist%40mail.maclaunch.com/> Using a Macintosh? Get free email and more at Applelinks! <http://www.applelinks.com>
