Cathode Corner SCTV, Инструкция по сборке и эксплуатации

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SCTV Clock Assembly Manual 1/24/22 12
positive hole with a + sign. The positive leads of the capacitors are longer. So put the long leads into the
plus holes. Bend the legs apart to hold them while soldering. Trim the excess lead length.
16) Install self-resetting fuse F1, bending the legs apart to hold it in place. Solder it. Trim the excess lead
length.
17) Install and solder the 1000uF capacitor C3 next. Put the long lead into the hole near the + sign. Trim
the excess lead length.
18) Install the rotary encoder S1. It snaps into place in the two large holes. Use care when snapping it
into place, so that all the small legs go into their holes. Ensure that it is aligned perpendicular to the
board, then solder it.
19) Install T1 next. You may have to straighten the leads to get them all to go into their holes. Make sure
it sits straight on the board, which may require work since one corner tends to sit higher than the others
due to the wires underneath it. Solder one pin on each side, then adjust it, then solder the remaining pins.
Trim the excess lead length.
20-21) Mount the heat sink for U1 using the two #4x1/4" self-tapping screws. Orient it with the notch
towards the board and the flat surface at the top. Blow all the metal filings off the board.
22-26) Put the 4-40 x 5/16” screw through the top hole of the heatsink from the capacitor side. Place the
beige thermal pad onto the screw. Place U21 into the holes in the board and onto the screw, while
holding the screw in place. Place the lockwasher and nut on the screw. Tighten the screw snug but not
real tight.
Solder the pins on U21.
27) A late change to the design has added a 7805 regulator IC to the bottom of the board, to improve
reliability of the power-on sequence. Remove the heat sink screw closest to the end of the board. Install
the 7805 regulator IC under this screw, with the legs over the F1 pads. Bend the leg without the
capacitor down so that it contacts the top of the F1 lead. Solder this pin to the F1 lead.