User Guide

( ) Connect the HEAVY BLUE wire coming from the high voltage feed-through insulator on the

left to hole “J” and solder.

( ) Connect the BLUE wire coming from the bottom of the capacitor bank (the + wire) to hole

“H” and solder.

( ) Connect the BLACK wire coming through the grommeted hole in the chassis (from the

relay contact) to hole “E” and solder.

( ) Connect the ORANGE wire coming from the meter switch to hole “G” and solder.

( ) Connect the YELLOW wire coming from the meter switch to hole “F” and solder.

( ) Connect the BLACK wire coming from the plate meter to hole “C” and solder.

( ) Connect the RED wire coming from the plate meter to hole “A” and solder.

( ) Connect the BLACK wire coming from the top of the capacitor bank (B- wire) to hole “B”

and solder.

( ) Connect the bare wire of the 0.001µF 6KV capacitor to hole “K” and solder.

( ) Carefully inspect all solder joints to be sure that both the joint is good and that there are no

solder bridges which could short components together. There are very high voltages on

this board.

( ) Attach the RM-220 circuit board to the tapped spacers using the previously saved (4) 6-32

x ¼” screws.

( ) Place the front panel back in place and loosely put in the 2 Phillips-head screws on the left

side of the front panel.

( ) Loosely reinstall the nut and washer holding the band switch to the front panel.

( ) Place the right side panel in position and hold it in place with the 4 previously removed

sheet metal screws.

( ) Reinstall the 2 right side Phillips-head screws in the front panel. Tighten all screws in the

front panel and the nut securing the band switch.

( ) Reinstall the 6-32 screw, nut and washer on the right rear top of the back panel.

( ) Replace the perforated cover and top rear plate cover. Reinstall the 15 sheet metal screws

holding these pieces in place. DO NOT over tighten these screws, as it is fairly easy to

strip the screw threads in the aluminum underneath.

( ) Reinstall the 3 large knobs on the front panel. Be sure that your pointer orientation is

correct on these knobs.

( ) Use the book to hold the amplifier while you reinstall the case and feet.

This completes the installation of the RM-220 rectifier and metering board. It will provide

you with protection from diode failure, as well as providing much more accurate meter readings.