Warner PC-505B - Checkout Procedures - AC, Auto Zero, and Vc Commands; Internal AC Voltage and Auto Zero Verification; Vc Commands Verification

PC-505B Manual, Rev. 201013
Warner Instruments
A Harvard Apparatus Company
23
13. Set oscilloscope to 5 mV/div.
14. Verify that METER reads 1 mV and that oscilloscope reads 10 mV (2 div at these settings).
15. Return amplifier to initial settings.
Internal AC voltage command checkout
1. Set COMMAND SELECT (COMMANDS block) to internal command.
2. Set COMMAND SENSITIVITY to x0.1
3. Set COMMAND SENSITIVITY toggle to on.
4. Connect V
c
x10 output BNC to oscilloscope.
5. Set oscilloscope voltage base to 0.5 V/div and time base to 5 ms/div.
6. Verify that oscilloscope displays appropriate square wave (1 V p–p at line local frequency
of 50 or 60 Hz).
7. Return amplifier and oscilloscope to initial settings.
Auto Zero control checkout
1. Disconnect voltage source from COMMAND IN BNC.
2. Connect model cell to headstage in patch mode.
3. Set METER SELECT to I
m.
4. Set PROBE RESISTER to high
5. Set COMMAND SENSITIVITY toggle to off.
6. Set COMMAND SELECT (COMMANDS block) to external command.
7. Use JUNCTION ZERO control to set I
m
output on METER to +10 pA.
8. Switch AUTO ZERO on and press AUTO ZERO BUTTON until meter reads zero.
9. Switch AUTO ZERO off.
10. Re–zero I
m
output using manual JUNCTION ZERO control.
11. Return amplifier to initial settings.
 Vc commands checkout
1. Connect model cell to headstage in patch mode.
2. Connect I
m
output BNC to oscilloscope.
3. Set oscilloscope to 1 V/div.
4. Set METER to I
m
.
5. Verify PROBE RESISTER is set to high.
6. Set COMMAND SELECT to external command.
7. Set COMMAND SENSITIVITY toggle to off.
8. Set VOLTAGE HOLD to positive (+).
9. Use VOLTAGE HOLD to set I
m
output to +10 pA on METER (positive hold adjustment should
give positive current output).