About a month ago, I bought non-working CDTV.
Actually, CDTV are booting fine into CDTV or Floppy menu, but no CD spinning & PSU fan ain't working.
After some restoration (cleaning, rust removal, CD & PSU recap...), I noticed that the power supply still was not working properly.
After that, I did some measurements and found that the +12v and -12v had failed.
+12v has only about +2v
and -12v has +0.5v
By having 2 other working devices, I took out PSU from a working one and tested it at the non properly working CDTV.
With this one, CDTV working as it should. CD booting fine and PSU fan are spinning.
I thought that the (main)coil had something:
Did a swap, but working PSU remain ok
and non-working, with the other know working coil, has still no +12 and -12v.
What else could it be?
Those transistors ie. Schottky diodes?
From left to right:
C3852,
MA756,
K1257,
MA649 and one more
C3852
I've already done a bit of research. But all of them can't be (MA756) or are hard to find.
Some on Aliexpress - but have to wait about 2 months and what quality
Are there (Mouser, Reichelt, Conrad) new comparable models that I can use?
Could be they a problem anyway? Or is there something else dead?
Didn't want to swap them one by one, from a good one. Like that Coil. But if there is no other way, I'm gonna do that too.
Any help will be appreciated.
Thanks for your time.
Actually, CDTV are booting fine into CDTV or Floppy menu, but no CD spinning & PSU fan ain't working.
After some restoration (cleaning, rust removal, CD & PSU recap...), I noticed that the power supply still was not working properly.
After that, I did some measurements and found that the +12v and -12v had failed.
+12v has only about +2v
and -12v has +0.5v
By having 2 other working devices, I took out PSU from a working one and tested it at the non properly working CDTV.
With this one, CDTV working as it should. CD booting fine and PSU fan are spinning.
I thought that the (main)coil had something:
Did a swap, but working PSU remain ok
and non-working, with the other know working coil, has still no +12 and -12v.
What else could it be?
Those transistors ie. Schottky diodes?
From left to right:
C3852,
MA756,
K1257,
MA649 and one more
C3852
I've already done a bit of research. But all of them can't be (MA756) or are hard to find.
Some on Aliexpress - but have to wait about 2 months and what quality
Are there (Mouser, Reichelt, Conrad) new comparable models that I can use?
Could be they a problem anyway? Or is there something else dead?
Didn't want to swap them one by one, from a good one. Like that Coil. But if there is no other way, I'm gonna do that too.
Any help will be appreciated.
Thanks for your time.
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