This Bogner repair was sent over all the way from Liverpool on the recommendation of a Liverpool tech who makes fantastic boutique point to point gear, but doesn’t deal much in modern technology.
The issue was with the DC heater supply which uses a switch mode power supply. Mr Bogner decided to use a switch mode to reduce weight in the amplifier.
The first stage was to verify that the amp worked with an external power supply: here’s a video of the first tests.
The Liverpool tech had already done some work on the output stage. My work on the SMPS was completed fairly quickly and it’s waiting to head back on the 100+ mile trip to Liverpool.
If you need a BOgner repair, please get in touch