WhitakerAudio 60 W Stereo Power Amplifier, Руководство пользователя и по сборке

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Automatic Protection Option – 40 /60W Version
– Install RYL202, RYL204 – DPDT, 10 A, 120 V ac, relay .
Examine the fuse holder. Some devices have a small plastic pin protruding from the mounting
side. This pin must be clipped off or the holder will not mount flat against the PWB.
– Install the fuse holder using the #4 hardware provided. Use short bare connecting wires
from the terminals to the pads on the PWB. Solder in place. Tighten the set screw (do not
over-tighten). Note that a 3/8-inch #4 standoff is used for the mounting nut.
A method that works well for the above step is to first mount the fuse block with the hardware
finger-tight. Then feed the bare wire up from the foil side of the board and affix it to the terminal.
Solder and then repeat for the other side of the component. Finally, tighten the mounting screw.
– Find the 0.5 A fuse. Install in the socket.
– Install the power transformer – Transformer, PC mount, 120 V ac primary, 25 V ac
secondary . Orient the device so pin #1 lines up with the square mounting pad. Solder in
place.
– Using the #4 hardware provided, attach 3/8-inch long #4 standoffs in each corner of the
PWB. Use a lockwasher directly under the screw head. Tighten.
Assembly of the Automatic Protection PWB has now been completed. Double-check your
work. The completed PWB is shown in Figure 3.
5.2 Installation
The Automatic Protection option is intended to be installed after the amplifier has been assembled
and tests completed. In cases where this option is installed on a new amplifier, a small amount of
rework is needed.
– Disconnect the amplifier from the ac power source. Remove the bottom panel.
– Remove the tubes and set them aside in a safe place. Remember to keep the output tube
pairs together.
– Remove the acrylic cover and chrome spacers.