Simpson 650 - Page 10

GENERAL DESCRIPTION
the front panel. The potentiometer is adjusted for
a ZERO reading, which indicates a balanced
condition of the bridge circuit when the collector
current 15 1.0 milliampere. The switch extends the
ZERO ADJ. range by shorting or connecting a
resistor in series with the potentiometer.
TRANSISTOR TEST SOCKET
The socket at the top center on the front panel
15 the transistor test socket. Before inserting the
transistor to be tested, be certain the emitter,
base and collector of the transistor are properly
identified. The emitter is inserted into the jack on
the left side, the base is inserted into the adjacent
jack, and the collector is inserted into the jack
on the right side. There is no connection to the
bottom jack of the transistor test socket.
E — B — C JACKS
Three jacks are located at the bottom right side
on the front panel, labeled E, B, and С.
In some instances, it may be convenient to
insert a transistor with long leads into the tran-
sistor test socket. Thus, the terminals of the
transistor test socket are also connected to the
three jacks marked E, B, and C for the emitting
base, and collector respectively.
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