WhitakerAudio JC Whitaker 20 W Stereo Integrated Audio Amplifier, Manual

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20 W Stereo Integrated Audio Amplifier
The amplifier PWBs are connected to the chassis through the mounting holes for the vacuum
tubes. Additional supporting posts are provided at each corner of the board.
The tube sockets are conventional chassis-mounted devices, with jumper leads extending
from the active pins to the PWB. The sockets are held away from the PWB using standoffs. This
approach permits the sockets to be firmly mounted on the chassis, rather than being physically
supported by the PWB. This approach also keeps heat above the chassis and away from the PWB,
which can degrade over time due to excessive heat.
Hot-3 AC hot buss Black Connects to ‘arm’ of RYL51
Hot-4 AC hot buss Blue Connects to blue primary lead from T51
Hot-5 AC hot buss Black Connects to black primary lead from T51
Hot-6 AC hot buss VR54
Hot-7 AC hot buss NC
Hot-8 AC hot buss White Connects to pilot light PL51
NC Not connected Blue/yellow Connects to blue/yellow primary lead from T51
NC Not connected Brown/yellow Connects to brown/yellow primary lead from
T51
NC Not connected Black/red Connects to black/red primary lead from T51
NC Not connected White/black Connects to the white/black primary lead from
T51
NC Not connected NC
NC Not connected NC
GND Ground Black Connects to main chassis ground point
6VH1 6 V ac heater Green Connects to the 6VH1 post on Amplifier PWB
#2 (left)
6VH2 6 V ac heater Brown Connects to the 6VH1 post on Amplifier PWB
#2 (left)
PL1 Plate from V2 Blue Connects to blue lead from T1
SC1 Screen from V2 Blue/yellow Connects to blue/yellow lead from T1
PL2 Plate from V3 Brown Connects to brown lead from T1
SC2 Screen from V3 Brown/yellow Connects to brown/yellow lead from T1
T1ct B+ to output transformer Red Connects to red lead from T1
Table 3.1 Amplifier PWB #1 (right) Connection Wiring Codes
(Note that the color codes for the transformers listed in this table may vary. Consult device
documentation before proceeding.)