WhitakerAudio J C Whitaker 20 W Stereo Audio Amplifier, Manual

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105
20 W Stereo Audio Amplifier
– Connect 50V – plate winding bias tap. Find the violet lead from the power transformer.
Install a connector to the wire. Attach to the 50V post on the rectifier PWB.
– Connect T51CT – plate winding center tap. Find the red/yellow lead from the power
transformer. Install a connector to the wire. Attach to the T51ct post on the rectifier PWB.
– Connect 6VH1 – 6.3 V filament. Find one of the green leads from the power transformer.
Install a connector to the wire. Attach to the one of 6VH1 post on the rectifier PWB.
– Connect 6VH2 – 6.3 V filament. Find the remaining green lead from the power
transformer. Install a connector to the wire. Attach to one of the 6VH2 post on the rectifier
PWB.
– Connect 6VHct – 6.3 V filament center-tap. Find the green/yellow lead from the power
transformer. Install a connector to the wire. Attach to the 6VHct post on the rectifier
PWB.
It is unlikely that the 5 V heater leads (yellow, yellow, black/yellow center-tap) will reach
their respective terminal posts on the left channel PWB. These leads will therefore need to be
extended. Use the following procedure.
– Cut two 11-inch long pieces of #22 yellow wire. Attach a quick-disconnect terminal to one
end of each wire. Attach a male quick-disconnect terminal to the free end of each wire.
– Connect 5VHa – 5 V heater. Connect one of the yellow wires to the 5VHa post on the left
channel PWB.
– Connect 5VHb – 5 V heater. Connect the remaining yellow wire to the 5VHb post on the
left channel PWB.
– Twist the yellow wires together along their length and route to the rectifier PWB.
– Find one of the yellow lead from the power transformer. Install a quick-disconnect
terminal to the wire. Mate with one of the yellow wires from the left channel PWB.
– Find the remaining yellow lead from the power transformer. Install a quick-disconnect
terminal to the wire. Mate with the remaining yellow wire from the left channel PWB.