Hello,
Just last week end my Philips VG-8235/20 stopped working. I have switched it off, removed the cartridge, re-inserted the cartridge and switched it on again. The computer did not boot up and the power LED remaind dark as well.
In the meantime I have checked the PSU output.
The +12 V works fine, but on -12 V there is basically nothing and on +5 V only about +2.6 V are achieved and not stable either.
I am now not sure what the specific problem is. Looking at the circuit diagram I see that both on -12 V and and +5 V there are capacitors so they might be faulty. In contrast, on +12 V there are no capacitors and that might be the reason why this still works.
On the other hand it appears to me that in the end both -12 V and +5 V are fed by the voltage regulator STK7561A.
Does anyone have an idea how to narrow down the problem ?
Thank you very much.
