1T910AD Germanium Power Amplifier

The amplifier is made according to the classical germanium amplifier circuitry of the USSR 60s-70s with single power supply. Standby power supply, soft Start device, delayed headphone connection (Delay Unit), as well as DC protection at the output (Protection Unit) are already traditional features of any amplifier. The amplifier power supply unit is made in a classic way: a separate secondary winding for each channel, D7 diodes, Epcos power supply capacitances. Transistors 1T910AD are installed at the output of both channels.

The amplifier printed circuit board is made with film photoresist technology. After printing the template with a laser printer, you can see how the polygons on the board are loosely blackened. But after applying the "Density Toner" spray, the polygons darken significantly and the template is ready to be placed in a UV bath. In the photo, I show you three fragments of the template before and after applying "Density Toner".

The amplifier is placed in the case of the "Vector" factory amplifier with modifications and changes. Use "Lightspeed Passive Attenuator" as the volume control. Variable resistor for adjustment - precision ALPS RK09L with a resistance of 100k. Very smooth and comfortable volume level up/down by ear.