Clint
Experienced Member
So I have a recent acquisition of 5160 With 5154 Colour Monitor, purchased from ebay both items from the same seller both advertised as dead and not working.
This one was born on 5th December 1984, in Scotland UK.
I did not try powering this on as it was quite dirty inside, it had been shipped with polystyrene around it but I was lucky and landed in perfect condition, I decided to strip it down and then rebuild it before trying it, on the way checking things for obvious issues.
I decided to recap the PSU, the RIFA's were cracked although not blown, I noticed a purposely cut track on the PCB, anyone know why this was done ?
After everything was clean I put it back together, I think its cleaned up very nicely
The HDD was not parked, I wonder if it will be ok?
I tried to turn it on but it did not work, I noticed the fan turned slightly which was a good sign. I stripped it back down to motherboard only and it started, after a little more fiddling I realised the FDD was the problem. With a multimeter set on ohms, I found the 12v rail was shorted to earth, a quick traceback found a 4.7uf 16v tantalum capacitor sitting at position C43 that was short, I filled the gap with a 4.7uf very low ESR Panasonic FC series capacitor.
Once done without the CGA/Parallel card installed the machine gave post beeps a great sign. I rebuilt the rest of the unit to await further testing once I have a keyboard and a display.
Here are the ISA cards that were installed (I forgot to photo the HDD controller) :
Now onto the monitor next, it is a 5154002 - the PSU is just doing a high pitched noise and no HT.... I took a brief look but they really didn't want and components to escape its in a serious metal cage, its going to take some getting at.
So I am guessing the PSU either has a fault or the HT circuit has a short and the PSU is shutting down as soon as it tries to start, either way I am guessing there will be a few components in that PSU that will need to be replaced due to age.
This one was born on 5th December 1984, in Scotland UK.
I did not try powering this on as it was quite dirty inside, it had been shipped with polystyrene around it but I was lucky and landed in perfect condition, I decided to strip it down and then rebuild it before trying it, on the way checking things for obvious issues.
I decided to recap the PSU, the RIFA's were cracked although not blown, I noticed a purposely cut track on the PCB, anyone know why this was done ?
After everything was clean I put it back together, I think its cleaned up very nicely
The HDD was not parked, I wonder if it will be ok?
I tried to turn it on but it did not work, I noticed the fan turned slightly which was a good sign. I stripped it back down to motherboard only and it started, after a little more fiddling I realised the FDD was the problem. With a multimeter set on ohms, I found the 12v rail was shorted to earth, a quick traceback found a 4.7uf 16v tantalum capacitor sitting at position C43 that was short, I filled the gap with a 4.7uf very low ESR Panasonic FC series capacitor.
Once done without the CGA/Parallel card installed the machine gave post beeps a great sign. I rebuilt the rest of the unit to await further testing once I have a keyboard and a display.
Here are the ISA cards that were installed (I forgot to photo the HDD controller) :
Now onto the monitor next, it is a 5154002 - the PSU is just doing a high pitched noise and no HT.... I took a brief look but they really didn't want and components to escape its in a serious metal cage, its going to take some getting at.
So I am guessing the PSU either has a fault or the HT circuit has a short and the PSU is shutting down as soon as it tries to start, either way I am guessing there will be a few components in that PSU that will need to be replaced due to age.