AC INPUT ADJUSTMENT

TM 11-5820-918-13

5-40. +27.1 VDC REGULATORS. The five potentiometers for adjustment of the +27.1

VDC regulators are R31, R33, R35, R37, and R39, located on the power regulator

assembly 2A2A4 (figure FO-34). R35 adjusts the driver amplifier supply. To measure

27.1 VDC 0.2, connect a voltmeter to 2A1J4 as follows: J4-B for R31; J4-A for R33;

J4-E for R35; J4-C for R37; and J4-D for R39. If adjustment is required, perform

the following steps:

Disconnect connectors 2A1J1, J2, and J3.

b. Remove the ten screws securing the 2A1 assembly to the 5018 chassis, and lift

out 2A1.

Connect a jumper between the 2A1 assembly and 5018 chassis.

d. Adjust potentiometers R31, R33, R35, R37, and R39 while measuring their re-

spective voltages at 2A1J4.

5-41. AC INPUT ADJUSTMENT. Variations in line voltage can be accommodated by adjust-

ing the position of taps on the transformer primary. The adjustment is made on as-

sembly 2A2 (figure FO-34) by unsoldering the standard 115/230 volt connections at

pins 4 and 9 of T1 and moving higher or lower in voltage as required. With voltages

less than 110 or 215 volts anticipated, move connections on respective primary taps

to pins 3 and 8. With voltages greater than 120 or 250 volts anticipated, move con-

nections to pins 5 and 10.