Augustica
®
T e c h n o l o g i e s
Page 6 of 7
substantially higher values of the AC component present in the high B-plus DC voltage,
your MOSFET transistor is probably burned out and it has to be replaced. Otherwise, the
MOSFET transistor is regulating and filtering the high B-plus DC voltage properly and
now you can solder to the PCB the heatsink on which the MOSFET transistor is situated.
Fourth, assemble the low DC voltage (filament) bus of the power supply and start with
attaching IC2 LD1084V low drop voltage regulator to its heatsink. Once you attached the
LD1084V to its heatsink, you can insert heatsink leads and LD1084V leads into the PCB.
Solder the regulator's IC2 leads to the PCB. At this point do not solder the heatsink's
leads to the PCB - you will do it later.
Fifth, solder the rectifying bridge D8-D11 and capacitors C21, C22, C23, and C24. Pay
attention to the polarity of the bridge D8-D11. Connect a transformer or variac to the
terminal block K3 and slowly bring AC voltage to 8 Volt AC. Measure the DC voltage
produced by the rectifying bridge D8-D11. If you applied 8 Volt AC to the rectifying
bridge, you should obtain about 11 Volt DC after rectification.
Sixth, solder diodes D12 and D13 and then solder resistors R28 and R29 followed by
capacitors C25, C26, C27, C28, C29 and C30. Now solder green LED D14 and resistor
R30. Connect a transformer or variac to the terminal block K3 again and measure the DC
voltage produced by the low voltage bus of the power supply as a whole. If you applied 8
Volt AC to the terminal block K3, the power supply should deliver about 11 Volt DC.
Measure AC component that is present in the filament DC voltage after it is regulated and
filtered by the IC2 LD1084V. The AC component of the filament DC voltage should be
about 0.6 millivolts AC. If your measurements show substantially higher value of the AC
component present in the DC voltage, your IC2 LD1084 is probably burned out and it has
to be replaced. Otherwise, the LD1084V is regulating and filtering the filament DC
voltage properly and now you can solder to the PCB the heatsink on which the LD1084V
is situated.
Seventh, solder resistors, capacitors and tube socket of the left channel of the headphone
amplifier Corvette
®
. Start with the tube socket, followed by the resistors and the
capacitors. Finally, solder volume control potentiometer R1, headphone stereo jack, and
terminal block K1.
Grounding of the volume control potentiometer is required as without it, the amplifier
Corvette
®
may be subject to noise and/or interference. Cut out a wire having length of at
least 15 centimeters. Strip out isolation from the wire. Wrap the wire around the threaded
portion of the potentiometer's neck making two loops and after that twist together the two
ends of the wire. Put on washer and nut included in the kit together with the
potentiometer R1. Solder the wire to the ground pad on the bottom side of the PCB.
Eighth, solder resistors, capacitors and tube socket of the right channel of the headphone
amplifier Corvette
®
. Start with the tube socket, followed by the resistors and the
capacitors.
