By belzrebuth
Fri Nov 11, 2016 11:44 am
Hi all,
I just got an MPC 2K from a friend that used to work fine.
Friend complained that suddenly the MPC stopped responding and displayed the classic symptom where the screen lights up but displays nothing and all leds on the top board lit,floppy led is also constantly on.
I've just checked the power supply and the 5V gives about 64ohm resistance to ground.
Is this normal?
Voltages are correct but I'm worried about the low resistance to ground which is persistent btw so that's not an intermittent short.
Low voltage caps look okay but I haven't lifted the power supply to check it thoroughly.
12V and -12V (I guess these are for the op-amps) are about 340-350 Ohm to GND.
I tried unplugging the top board,the screen inverter board,the floppy,reseating roms but I get nothing on the screen.
No expansions are installed.
The two simm slots are unpopulated so I guess there must be on-board memory somewhere else.
I don't have any schematics and I'm totally unfamiliar with this machine so any clue would be of value.
Here is a link to pictures showing what's going on with the power supply:
https://www.dropbox.com/sh/30jy2kzrzij1 ... M1T9a?dl=0
I just got an MPC 2K from a friend that used to work fine.
Friend complained that suddenly the MPC stopped responding and displayed the classic symptom where the screen lights up but displays nothing and all leds on the top board lit,floppy led is also constantly on.
I've just checked the power supply and the 5V gives about 64ohm resistance to ground.
Is this normal?
Voltages are correct but I'm worried about the low resistance to ground which is persistent btw so that's not an intermittent short.
Low voltage caps look okay but I haven't lifted the power supply to check it thoroughly.
12V and -12V (I guess these are for the op-amps) are about 340-350 Ohm to GND.
I tried unplugging the top board,the screen inverter board,the floppy,reseating roms but I get nothing on the screen.
No expansions are installed.
The two simm slots are unpopulated so I guess there must be on-board memory somewhere else.
I don't have any schematics and I'm totally unfamiliar with this machine so any clue would be of value.
Here is a link to pictures showing what's going on with the power supply:
https://www.dropbox.com/sh/30jy2kzrzij1 ... M1T9a?dl=0
Last edited by belzrebuth on Fri Nov 11, 2016 4:40 pm, edited 1 time in total.