Augustica
®
T e c h n o l o g i e s
Page 8 of 9
Now, set aside the power supply's PCB and start soldering the headphone amplifier's
PCB.
A
SSEMBLY OF THE
A
MPLIFIER
PCB
Tenth, solder resistors, capacitors, diodes and tube sockets of the left channel of the
headphone amplifier Frigate
®
. Start with the tube sockets, followed by the resistors,
capacitors, and diodes. Finally, solder volume control potentiometer R1, headphone
stereo jack, and terminal block K1 of the amplifier.
Grounding of the volume control potentiometer R1 is required as without it, the amplifier
Frigate
®
may be subject to static noise or radio frequency interference. Cut out a wire
having length of at least 15 centimetres. 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
amplifier's PCB.
Eleventh, solder resistors, capacitors, diodes and tube sockets of the right channel of the
headphone amplifier Frigate
®
. Start with the tube sockets, followed by the resistors,
capacitors, and diodes.
Before testing the headphone amplifier Frigate
®
, visually inspect the amplifier's PCB for
breaks in symmetry between the left and right channels.
T
ESTING
First, attach only low voltage (filament) power supply’s transformer leads to the terminal
block K3 of the power supply's PCB, leaving the other set of the filament transformer
leads, and the high voltage transformer leads unattached and electrical tape shrouded. Do
not install 6922 and 6H30Pi tubes in their sockets.
Second, apply the low AC voltage to the terminal block K3 in the left filament bus of the
power supply, while looking for smoke or part discoloration or bulging.
Third, attach the second set of the filament transformer leads to the terminal block K5,
while looking for smoke or part discoloration or bulging.
Fourth, using wire, connect the terminal block K4 on the power supply's PCB with the
terminal block K3 on the amplifier's PCB. Measure the filament voltage regulator IC2
LM1084V output voltage with the load provided by the left channel filament bus of the
amplifier Frigate
®
. If the filament voltage regulator IC2 LD1084V fails to regulate, try
either lowering the filament voltage a tad, or increasing it a tad, for example try 16 Volt
