My monitor just went black (still power going to it and you can see if turn on and off). No 5v through the jamma loom, nothing playing blind with audio. Tried a couple of boards and my naomi but all the same, Naomi powers up. Fuse looks ok on the PSU. Not really sure where to go from there. No expert with electrics tbh.
Blast City issue
- Thread starter SIE
- Start date
Retroman839
Senior Member
No 5v …. It’s going to be either
Your blast city io
Or your blast psu ( it’s big and slides out the back when you remove 4 or six small screws ).
Once that is removed you need to open it to get to the psu .. then you can see if fuse inside the psu is blown ..
it may need some work like recapping .
Sega blast audio amplifier is also inside that box . You may quite as easily just lost Connectivity on the 5v try pushing the amp up connectors into the io see if that helps with machine off of course 👍…
Best thing is you monitor sounds to be fine you’ve just lost power to the jamma connector . If you can use a multi meter you could try to see if you have 12v at the jamma edge connector
Your blast city io
Or your blast psu ( it’s big and slides out the back when you remove 4 or six small screws ).
Once that is removed you need to open it to get to the psu .. then you can see if fuse inside the psu is blown ..
it may need some work like recapping .
Sega blast audio amplifier is also inside that box . You may quite as easily just lost Connectivity on the 5v try pushing the amp up connectors into the io see if that helps with machine off of course 👍…
Best thing is you monitor sounds to be fine you’ve just lost power to the jamma connector . If you can use a multi meter you could try to see if you have 12v at the jamma edge connector
Did some work on it a few years ago and replaced the amp inside the PSU. Took the unit out and the fuse looks fine, can't see any damage although the power unit side of the PSU was pretty dirty. Can't see any signs of damage. I will test the 12v tomorrow.
Is there anywhere/anyone that services them? I sourced my amp from China last time to get the part. I'm not the best at soldering so don't fancy recapping myself.
Thanks for input.
Is there anywhere/anyone that services them? I sourced my amp from China last time to get the part. I'm not the best at soldering so don't fancy recapping myself.
Thanks for input.
Retroman839
Senior Member
Check if your getting 12v first .
Post some pics here tomo of the psu’s Caps We may see some
Suspect caps
Post some pics here tomo of the psu’s Caps We may see some
Suspect caps
Retroman839
Senior Member
Sounds like bad caps
Retroman839
Senior Member
Take the big heat sink off ..
Than you can see the caps better
Take a pic of the caps once heat sink is off.
Your lucky you haven’t had a pcb damaged . 5v could have gone up.
Like the 12v has doubled .. that’s caps
Than you can see the caps better
Take a pic of the caps once heat sink is off.
Your lucky you haven’t had a pcb damaged . 5v could have gone up.
Like the 12v has doubled .. that’s caps