30
+10.000VDC reference is generated on the
"bottom" PCB.
REAR PANEL OUTPUT DRIVERS
The /02 option provides rear panel outputs for
the T0, A, B, C and D outputs with an amplitude
of 8x the corresponding front panel output. Each
of the five output drivers are the same, the
description which follows references channel
A's output.
An ECL level signal indicating the end of delay
for channel A is applied to the base of Q3A. The
amplified pulse is coupled through T1A to the
base of the Darlington pair, Q2A and Q1A. Q1A
is saturated, shorting its collector to its emitter.
The relay on the output is shown in the position
for positive output pulses. When Q1A is turned on,
the capacitors C4A and C5A, which were charged to
-20 VDC through R9A, are connected to the
capacitors C2A and C3A, which were precharged to
a voltage from - 19 to +20 VDC by the op amp 2/2
of U1. The output will pulse high from 1 to 40Volts,
depending on the precharge of C2A and C3A. The
pulse will last until the core of the transformer,
T1A, saturates.
The op amp, which precharges C2A and C3A, is a
linear differential amplifier, which senses the
amplitude current source for the corresponding front
panel output. The average current output from the
rear panel outputs is limited by the 1 K
Ω
charging
resistors, R5A and R6A. These resistors also reduce
the amplitude of the outputs by 2 Volts per
milliampere of output current.
