WhitakerAudio J C Whitaker 20 W Stereo Audio Amplifier, Руководство пользователя

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– Find the black #18 wire from the right channel PWB. Attach a quick-disconnect terminal
and connect to the H-7 post on the preamplifier power supply PWB.
– Find the #22 black wire from the rectifier PWB GND post. Attach to the available GND
post on the preamplifier power supply PWB.
– Find the #22 600 V red wire from the rectifier PWB B+ terminal. Attach to the B+ post on
the preamplifier power supply PWB.
5.7 Final Assembly Check
The 20 W Stereo Amplifier has now been completed. Make a thorough visual inspection to make
sure everything looks OK. All parts should be installed, with the exception of the vacuum tubes. If
you have any parts left-over, recheck the procedures documented here and install the part(s) as
needed. Figure 5.15 shows the chassis view of the 20 W Stereo Amplifier. Various detail views of
the assembled amplifier are shown in Figure 5.16.
Shields are provided for the input pentode/triode stages (V1 and V4). Installation of the
shields is recommended, but not strictly required. The shields are available in three colors: blue,
red, and black. Blue is provided with this unit.
Install the two 9-pin tube shields as follows:
• Remove the chassis mounting screws from the V1 and V4 sockets.
• Separate the base of the shield from the shell and mount the sockets using the #4 screws.
• Set the shells aside; they will be installed later.
Turn the chassis over to remove any debris or loose items laying in the chassis.
Find the three “caution” stickers. Install them as follows:
• “Warning Hazardous Voltages Inside” – bottom chassis plate, facing outward so it is
visible when the plate is installed.
• “Warning Risk of Electric Shock” – on the side of the chassis adjacent to the right channel
PWB (inside the chassis).
• “Danger High Voltage” – on the power management PWB, foil side; avoid line traces.
Before proceeding to Initial Checkout, it is recommended that builders clean up the
workspace and put away all tools. An occasional “workbench reset” is useful for any project.