Mine stopped the same way. I gently spread the boards apart and unsoldered the 3 pin regulator then added a Red-LED in place of the three links (Original circuit had three diodes) and my monitor starting working again. So it may be recoverable.
Regards Randall -----Original Message----- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On Behalf Of Steve Sent: Monday, 6 June 2011 11:34 a.m. To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] fluke.l monitor for Thunderbolt Thanks everyone for the advice, both on and off list. I do see voltage transitions on P0.5 of the C8051F330D, which is pin 19 on the DIP version of the microprocessor. So it appears that the serial data pulses are making it from the Thunderbird to the input to the microprocessor. However, voltage as measured from the microprocessor VDD to GND (pins 6 to 5) is 4.94VDC. The C8051F330D manufacturer's spec for VDD is 4.2VDC "Absolute Maximum Rating." Didier's speculation seems on point . . . overvoltage on the microprocessor has likely damaged it. There is a caveat: The way the iCruze is constructed has the C8051F330D sandwiched between two PCB's and not readily visible. So I am assuming that the microprocessor is a C8051F330D, but that is not verified (at least not by me). Getting at the microprocessor requires desoldering the 16-pin header which connects its PCB to the display PCB. Not sure where to go from here . . . trash can? Steve _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.