Trying to repair an old tvv47 phono preamp

[Kay Pirinha]

You didn't understand me. Or didn't want to. I suggested doing my mods after having successfully solved the original issue.

Best regards!

 

[onokun]

Long story short, the preamp is now working perfectly.

I've replaced the power xformer, moved it to a separate small box along with rectifier diodes, added a fuse, a "power on" led, and a switch.
For the diode bridge protection I opted for an NTC resistor, hope that this will be enough.

The DC voltages of the preamp are spot on.

Thank you for all your suggestions, they are really helpful )

 

[Mooly]

Pleased to hear you found a solution 🙂 An NTC is OK for protection as long as the transformer is rated high enough to supply the continuous fault current needed to 'trip' the NTC and then to sustain that current.