6. TROUBLESHOOTING page
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Model PRM-470B
6.3. PRCB-001 BOARD
This section is a cross reference for adjustments and test points on the PRCB-001 computer
board.
Refer to "PCRB-001 Control Board Schematic Diagram" Drawing 4 and "PCRB-001 Control
board Component Designator" Drawing 5 (Appendix F.) to identify the PRCB-001 component
for the locations of the test points.
Refer to Parts (section Appendix E.1.) for information on parts ordering and replacement of the
PRCB-001 board assembly.
Test
points:
TP1: VCC test point (This should be 5.0 ±0.25Vdc.)
TP2: Ground
TP3: Counter input (This is the output of the LLD.)
TP4: Ground
TP5: Discriminator level (Pulses which do not cross this level
are not counted by the PRM.)
TP6: Pulse amplitude test point (This is used when setting up the instrument.)
TP7: Five volt regulator output (This becomes VCC after L1.)
Potentiometers:
R2: Audio tone adjustment (This is factory adjusted for maximum volume.)
R18: Discriminator adjustment
