Centipede ar2 voltages help

[Body pop]

My ar2 has just been rebuilt and put back in
This is the voltages I’m getting
The game was coming on before it was rebuilt ,so must be something I’ve done wrong fitting it back in
Getting neck glow on monitor and nothing else

Could anyone tell me the best place to start with it ?

36 vac - 17.85 I’m getting
-5 -5.21
12v. 11.72
+10.3. 13.01
+22. +23
Sense 0.85 Body pop2020-07-16 19:23:23

 

[Body pop]

Anyone ?

 

[yorkshire_spam]

Has it been sense mod'd ?
Are you getting +5V on the board? I doubt it with that sense reading.

 

[Body pop]

No mate ,getting 0.85 at the 5v on board
It was working before removing the ar2 to be serviced
But it did have occasional graphics errors and I wasn’t able to adjust the 5 v as the adjuster was faulty

 

[Body pop]

 

[Body pop]

I took the fuse holder cleaned it ,reseated everything
Checked fuses and continuity
What else could I check ?

 

[yorkshire_spam]

Sounds like something is borked on the ARII in the +5VDC supply circuit - I'll dig out the schematic and have a look at what the likely culprit might be

 

[yorkshire_spam]

Hmmm power supply circuits aren't really my area. As you have the 10.3DC unreg the problem is on the ARII not the brick.
Has the ARII had the sense mod hack done?

 

[Body pop]

 

[Body pop]

No sense mod .

 

[yorkshire_spam]

Ok, Does adjusting R8 make any difference?
Q1 looks correctly aligned, but worth checking that pin 4 on Q1 is directly connected to Pin 2 on J7 (- Sense) to make 100% sure that it's in right.

Also worth checking whether or not Q2 and Q3 should be grounded to the heatsink OR isolated from it - and make sure they are as they should be (sorry - from memory I'm not sure which way round it is with these)

I'd seriously consider doing the sense mod to protect the ARII and the PCB in future.

 

[acidburn]

I think that you might be measuring your 36VAC with your meter incorrectly. You don't want to use ground when testing the 36vac as it's AC not DC.

Where are you taking your measurement from?

 

[Body pop]

I’ve found out that the transistor on the heat sink is most likely duff
So getting it sorted and sense mod done
Thanks guys For your help .much appreciated