WhitakerAudio 60 W Stereo Power Amplifier, User And Assembly Manual

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60 W Stereo Power Amplifier
– Find the Grommets package. There are five 1/2-inch grommets. Install on the chassis at
the cable entry points for the output transformers and choke. Install the two 3/4-inch
grommets on the chassis at the cable entry points for the power transformer.
– Unpack the filter choke L51 and carefully position it on the chassis. Secure with the #6
hardware provided. Make sure to include the grounding lug under one of the rear pads.
Route the grounding wire through the opening for the choke leads.
5.4.5 Install Printed Wiring Boards
The following steps require patience. Do not force the boards and tube sockets into position, but
rather work them in carefully and slowly.
– Locate the right channel amplifier PWB. Remove the screws that secure the sockets to the
standoffs, and remove the screws in the standoffs in the four corners of the PWB (if
present). Set these in a convenient place.
– Check the heater wiring on the foil side of the board. Position so the wiring will rest
against the chassis when secured in place.
– Carefully place the right channel amplifier PWB in position from the underside of the
chassis.
– Install the six 4-40 x 3/8-inch mounting screws from the top of the chassis to the socket
standoffs on the circuit board. Some adjustment may be needed for the sockets to achieve
proper alignment. After the sockets are in position, install the four screws for the four
standoffs at the corners of the PWB. Do not tighten the screws until all screws have been
threaded and the sockets properly extend through the chassis cutouts so they are flush with
the top of the chassis.
– Repeat this procedure for the left channel PWB.
– Repeat this procedure for the power supply PWB.
– Once all PWBs have been installed, tighten by using two screwdrivers—one from the
bottom of the chassis and the other from the top. Turn in opposite directions. Be careful
not to over-tighten. Be careful to not scratch the top finish.