2005

(a)

Set CALIBRATE potentiometer R39 to the middle of

its range.

(b)

Disconnect any jumper wires connected across re-

sistors R9, R13, R40 and/or R41.

(c)

Connect jumper wires, in various combinations,

across resistors R9, R13, R40, and R41 until the

output is within 2.5 MV of zero. Solder the

jumper wires in these positions.

(d)

Adjust CALIBRATE potentiometer R39 for an output

of 0.000 volt ±1 MV.

c. 20—Volt Adjustment:

NOTE

Make this adjustment only after the zero

voltage calibration.

(1)

Set the RANGE switch to 10—20V and adjust the supply

output to 20.000 volts. Set the VERNIER control fully counterclockwise.

(2)

Check that the dots on the VERNIER control and front

panel are aligned. A setscrew is located in the VERNIER control for

any necessary adjustment.

(3)

Set the VERNIER control to 0.

(4)

Connect a high precision voltmeter across the output

of the supply.

(5)

Sot the AC switch to ON and observe the voltmeter.

(6)

If necessary, adjust potentiometer R12 (on the amplifier

board) until the voltmeter reads 20.000 ±0.007 volts.

d.

CURRENT LIMIT ADJ Range Adjustment:

(1)

Set the power supply output voltage to 20.000 volts.

(2)

Sot the meter switch to MA.

(3)

Set potentiometer R27 (on the amplifier board) to the

center of its range.

(4)

Adjust CURRENT LIMIT ADJ potentiometer R25 through its

entire range while depresseing CURRENT LIMIT SET pushbutton S3.

(5)

Adjust potentiometer R27 until the CURRENT LIMIT ADJ

potentiometer varies the output current from 0 to 500 MA over its

entire range.

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