1 Feb
2011
1 Feb
'11
12:24 p.m.
On 31/01/2011 21:24, "Tony Duell" <ard at p850ug1.demon.co.uk> wrote:
My first worry is that 5V line. If you had the logic PCBs connected and
it really is 6.2V, then you may well have damaged ICs... Most will stand
up to 7V, though , but I don't like to risk it.
IIRC the DRAms in a 380Z need the +12V and -5V supplies, which could
expaline why nothign is working with hte 12V rail missing. Have you
checked the votlages on the 10 pin connectors to the logic boards?
You have removed the seires bulb now, I hope. I
doubt the machine would
run with a bulb in seires with it.
OK, I've removed the bulb and checked the voltages on the floppy connector,
seems like the death of the 12V circuit is what caused the mains fuse to go.
+5V is reading +6.2 and +12V is dead. Looks like I'll finally have to remove the PSU from the case which will be fun as the
earthing screws on the rear
of the case have corroded quite badly.
Anyone got a schematic for the PSU?
Not that I know of, but I thought it was so simple (transformer +
rectifiers + smoothing caps + 3 terminal regualtors) that you didn't need
one. Or is there something odd about it?
Getting to my 380Z would be a problem, but if necessary I will get it out
and take it apart to check for you.
-tony