HP 5334B Service Manual page 190

e. Transceiver IC U7 may be checked with the following program:
NOTE
This test requires an input signal to the Counter. Connect the Time Base
output from the rear panel of the Counter to Input A.
The following program makes use of all the lines on U7. Check that the in-
puts match the outputs, and that the signals on pins
1, 7,
9, and 15 change
state.
BASIC Program:
10 CONTROL 7,16; 129, 13,lO
20 OUTPUT 703; "IN, FN1, GA.OO1, HS1"
30 ENTER 703 USING "%, %K";
X$
40 GOT0 20
50 END
RUN
8-437. Signature Analysis can be used to help troubleshoot the HP-IB Block. The instructions for using Signa-
ture Analysis to troubleshoot the HP-IB Block starts in paragraph 8-456, Signature Analysis.
8-438. OPTION 030 CHANNEL C TROUBLESHOOTING
8-439. The Channel C Input Amplifier Block consists of the following circuits: input signal conditioning,
amplifier, prescaler, peak detectorlthreshold comparator, and buffer. Refer to Figure 8-26, Channel C Input
AmpMer Block Schematic Diagram.
8-440. The output (U303 pin 1) of the three-stage Amplifier drives the Divider (U302) and Peak Detector
(CR302). The Peak Detector sends a signal to the Threshold Comparator (U306) that gates the output of the
Divider through the output Buffer (U301) to the rest of Counter. (The gating technique is used to prevent the
Counter from counting the random numbers that the Divider naturally produces, when the Divider has an insuffi-
cient input signal.)
NOTE
The Peak Detector circuit consists of two major active components: the
Peak Detector diode CR302 and Threshold Comparator U306, which is the
output of the Peak Detector circuit. Thus, throughout the remainder of this
troubleshooting procedure any mention of "Peak Detector" is referring to
both the Peak Detector CR302 and Threshold Comparator U306 and their
associated components.
HP 5334B
-
Service
Manual
8-70