4-6
Service
12. On the HV Board, short E501 and E502 together with a jumper
wire (Figure 4-4).
E502 and E501
/---- J5��------�soi/
HV IN ;-- .
�c=c"'c
=
�,==='===���""'
-HV RET E502
E501
R602----r;--;-- --;------��7
_1_ ____ _______ •
High ---+=l-----�----►�i5
=
=
=
=
Voltage
Board
--
E504_
High Voltage Board
OUT
Figure 4-4. Calibration Components on the HV Board
13. Short R602 (500Q, 100W mounted to the chassis) with a jumper
wire (Figure 4-4).
14. Connect a variable current source between E502 and the chassis.
15. Connect a power cord.
16. To check the gain of the amplifier, adjust the variable current
source for an output of 30 mA. Press the
CURR 5
key. Adjust
R310 on the CPU board (Figure 4-3) so the front panel display
reads 3.0 x 10 -
2
•
17. Check the following gains:
Current Source
Front Panel Display
300 mA
3.0
X
10
-l
±1 digit, ±5%
3 mA
3.0 x 10-
3
±1 digit, ±5%
300 µA
3.0 x 10
-4
±1 digit, ±5%
