Partial mechanical assembly of the kit provides protec- tion for major components during shipment. Most of the hardware thus used is included in the quantities listed in the parts list. The exception is that used to install the rear mounting bracket on the PC-14, as this is considered an in- tegral assembly. Only the two screws securing the bracket to the side pieces need be removed, along with the hardware securing the front sub-panel. Dismount the power transformer and remove the side pieces.
A “set” of hardware includes a screw and a KEP nut with attached lockwasher. Always install the lockwasher side first. Screws are always inserted from the outside of the chassis unless otherwise specified. #4 hardware is smaller in diameter than #6. To separate #4 nuts from the #6s, use a long #4 screw to test.
We suggest you check off the parts as you unpack the kit, and separate them in an egg carton for convenience.
10 The flanges of the front sub-panel bend towards the inside of the preamp. Select the U-shaped head- phone jack mounting bracket and 2 sets of #4 hardware. Install the mounting bracket on the out- side of the front panel, in front of the rectangular hole in the lower right comer.
2 0 Select the headphone jack, its washer and nut. Install it through the front panel with the single lug at the bottom. The washer goes outside the bracket, secured by the nut.
3 0 Prepare a 2” black wire. Connect one end to the lower forward lug of the headphone jack. (S). Place this wire through the panel.
4 0 Prepare a 14½” green wire, but strip 3/8” of insulation from one end. Prepare a 14½” red wire. Prepare a 14½” black wire. Start with the red wire ¼ ” longer than the longer bare end of the green wire, and the black wire ½” shorter than the green wire. Twist these 3 wires together uniformly throughout their length. Make about 3 com- plete twists every two inches. On the rear of the phone jack 8 numbered positions identify the 6 lugs in a counter- clockwise rotation, with the #2 lug at the bottom (in line
with the front lug), and the #6 lug at the top. Insert the
longer bared end of the green wire through the #8 lug and connect it to lug #7. Solder both lugs. Connect the red wire to lug #6. (S).
5@ Prepare another 14%” green wire with 3/8”stripped from one end. Prepare one end of a 14½” black wire. Do not strip the other end. Prepare another 14½” red wire. Start with the longer green wire end ¼” longer than the red wire, and the bare end of the black wire ½” shorter than the red wire. Twist these together as before. Insert the longer end of the green wire through lug #3 of the phone jack and connect it to lug #4. Solder both lugs. Connect the red wire to lug #2. (S).
6 0 Select the power switch and two #4 screws. Install the switch above the headphone jack so that the body of the switch is offset to the outer edge of the panel.
7 0 Select the main PC-14 circuit board assembly, with the fuse in place, and the rear bracket installed, and a rubber grommet in the bracket. Select the 6 larger nuts and washers for securing the controls to the front sub-panel. The two largest sets are used for the selector switches; the volume control is the smallest size, next to the power switch; the 3 other sets go on the 3 central control shafts. Be sure all the locating lugs on the controls engage the holes in the panel be- fore securing the hardware. The wires from the phone jack go under the board. Push the ends of the wires through the grommet.
8 0 Select the small circuit board assembly PC-13 and two #4 screws. With the circuit board uppermost, position the assembly at the top of the large front panel opening so that the sockets on the board align with the pins from below, and plug the board down- ward onto the pins. Make sure each pin is properly engaged. Secure the assembly with screws through the panel.
Set the front panel aside, and select the PC-12 circuit board. The front of the board marks the component locations, and “J” designations. Most components mount on the front. Always install them tight against the board, and solder each lead on the back (circuit) side. Then cut off all excess leads.
9 0 Select the two 22,100 ohm resistors (red, red, brown, red) and install them at locations R50 and R150.
10 0 Select the two 1,100 ohm resistors (brown, brown, black, brown) and install them at R21 and R121.
11 0 Install the four 1 megohm resistors (brown, black, black, yellow) at locations R22, R23, R122 and R123.
12 0 Select the two 4-pin molded sockets. These are to be installed at locations J26 and 5126 on the front of the board, with the pins through the upper row of holes (arrow) at each location. The lower row of holes provides access from the rear of the board for plug-in capacitors. lb assure correct alignment of the sock- et, insert a capacitor lead from the rear into holes E, F, G and H to engage the sockets while you solder the pins, and then remove the capacitors. Be sure solder flows freely around each mounting pin for a good connection. Sometimes these pins do not ac- cept solder easily.
13 0 The proper way to install the 24 phono input sockets is to first insert a phono plug (on the end of one of the audio connecting cables supplied in the kit) so that the center contact will not be deformed in the mounting process. Adjacent to the center hole for
