Pulsar TC-10B, Руководство пользователя

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8.1 Precautions When
Selecting Test Equipment
(See Chapter 4 for test equipment specifications.)
To prevent damage to solid-state components and
circuits:
1) Use transformer-type signal generators,
VTVMs and signal tracers, which isolate
the test equipment from the power line.
Whenever the test equipment uses a trans-
formerless power supply, use an isolation
type transformer. The test equipment
ground should be isolated from the ac
source ground.
2) Use multi-meters with at least 20,000
Ohms-per-volt sensitivity.
8.2 Precautions When Using
Test Equipment
1. Use a common ground between the chassis of
the test equipment and the transistor
equipment.
2. When testing transistors and diodes, give
special attention to the polarity of the meter
leads.
For example: When measuring the forward
resistance of a diode using a meter that has the
internal battery connected to the metering
circuit, be sure that:
• The lead marked ( + ) touches the diode
anode.
• The lead marked ( – ) touches the diode
cathode.
3. When checking circuits with an oscillographic
probe, be sure to discharge any built-up
capacitive voltage by touching the probe to a
ground before touching the circuit.
When individual module maintenance is required, either at the factory or at the customer installation
(beyond the scope of routine alignment), the following procedures are applicable.
Copyright © 2003 Pulsar Technologies, Inc.
Chapter 8. Maintenance
8
!
CAUTION
HIGH CURRENTS FROM A LOW-SENSITIVITY
METER CAN DAMAGE SOLID STATE DEVICES.
!
CAUTION
METERING TRANSISTOR CIRCUITS CAN
CAUSE DAMAGE. FOR EXAMPLE: A BASE-TO-
COLLECTOR SHORT DURING TRANSISTOR
OPERATION CAN DESTROY THE TRANSISTOR.