Tektronix 1710J Series, Инструкция по эксплуатации

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Maintenance
8–26
1710J-Series Waveform Monitors
1. Turn off the power supply. Use the diode check on the DMM to test CR1,
CR2, CR3, CR5, and CR6 for shorts.
2. Power up the power supply.
3. Using the DMM, measure the voltage between TP1 and the cathode of CR5.
It should vary between approxi75 and +200 V as R58 (CRT Bias) is
adjusted.
4. Connect the oscilloscope probe to the anode of CR5 and the probe ground to
TP1. The signal should be a clipped sinewave of +75 to +200 V
p–p
.
This is one of two procedures to perform if there is no CRT display.
1. Connect the oscilloscope probe to T1 pin 3 (Q6 collector) and the probe
ground to TP1. Power up the supply. The signal should be a +60 V
p–p
, 22
kHz sine wave.
2. Check the voltages listed in Table 8–8 using the DMM:
Table 8–8: High Voltage Oscillator Test Points
Circuit Location Voltage
T1, pin 4 Approxi40 V
T1, pin 13 Less than +2 V
U2, pin 2 Approxi4.8 V
U2, pin 6 +4 to +11 V
CR9, cathode Approxi100 V
This is the second procedure to perform if there is no CRT Display.
NOTE
. This check requires a high voltage probe having an input resistance of
1G
W
or more.
1. Connect the high voltage probe ground to TP1.
2. Load the low volts supply with the instrument, or with a 20
W
, 2 W resistor
loading the 5 V supply.
3. Power up the power supply.
4. Use the high voltage probe to measure the voltage at the anode of CR4. It
should be approximately –2350 V.
High Voltage Oscillator
Check
CRT Voltage Check