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Old 14th May 2021, 1:53 pm   #2
Join Date: Oct 2007
Location: Exeter, Devon, UK.
Posts: 1,398
Default Re: Faulty power Transformator - replacement?

Transformer troubles.
It certainly sounds as though the transformer insulation is failing., but first just check that the unit is bolted down firmly to the PCB and the laminations are firmly clamped together.
Are any windings connected together on the circuit board. I suspect the use is as 100-0-100v at 9ma to feed a nixie tube display, and 8-0-8 at 200ma for the main electronics. This latter is presumably rectified and cut down to a 5 v rail through a regulator IC, such as 7805. And perhaps a negative 5v rail through a 7905.
You must tell us a bit more about the circuit components around the transformer.
The primary is two 120v windings, so probably connected in series for UK mains. Perhaps you can confirm.
With this information, it should not be difficult to identify an alternative and any necessary mods to the PC Board.
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