Test Equipment Required; Checkout Procedures; Troubleshooting - HP 59501A Operating And Service Manual

SECTION V
MAINTENANCE
5-1 INTRODUCTION
5-2 This section contains checkout, troubleshooting,
repair and replacement, and adjustment procedures for the
59501A. The checkout procedures verify that the 59501A
circuitry is operating properly by checking that it can be
programmed by an HP-IB controller and that it is properly
adjusted. The troubleshooting procedures are performed if
a malfunction occurs while performing the checkout pro¬
cedures or during normal operations.
5-3 TEST EQUIPMENT REQUIRED
5-4 The controller (e. g., 9825A or 9830A calculator),
equipped with the appropriate bus interface card, provides
all of the signal inputs necessary for checking and trouble¬
shooting the 59501A The additional instruments required
for troubleshooting are listed in Table 5-1.
5-5 if available, Bus System Analyzer HP Mode! 59401A
can be used in place of the calculator when checking or
troubleshooting the 59501 A. The 59401A provides talker,
listener, and controller modes of operation. The operating
speed of the 59401A varies from one character at a time in
the halt mode, to two characters per second in the slow
mode, and full HP-IB speed in the fast mode. Thus, the
59401A can be used to exercise the 59501A circuitry allow¬
ing one character at a time to be transferred and checked.
5-6 CHECKOUT PROCEDURES
5-7 The procedures given in the flow chart of Figure
5-1 can be used to check operation of the 59501A when it
is initially received. If a malfunction is detected during
checkout, the procedures determine whether adjustment
or troubleshooting is required, The procedures in Figure
5-1 provide the following checks:
1. Output voltage is held near OV when power is applied.
2. Listen logic is enabled when the 59501 A's listen
address is received.
3. Listen logic is disabled when the interface clear (iFC)
signal 'is received.
4. Unipolar mode - zero output programming accuracy.
5. Unipolar mode — full scale programming accuracy.
6
. Bipolar mode - full .scale programming accuracy.
7. Listen logic is disabled when the ''Unlisten'' command
is received.
5-8 The checkout procedures are performed with the
59501A connected to the HP-IB along with a controller.
The 59501 A's address switches are set to and a DVM
is connected between the A1 and A2 output terminals.
Connect the DVM common lead to the A1 output terminal.
5-9 TROUBLESHOOTING
5-10 The troubleshooting procedures (Figures 5-2 through
5-4) assume that the controller is operating properly and that
a malfunction exists in the 59501 A. Before attempting to
troubleshoot the 59501A, ensure that the fault was not caused
by a programming error. Also, it is recommended that the
reader review the circuit descriptions provided in Section IV.
A good understanding of circuit operation will aid in
troubleshooting. In order to troubleshoot the 59501 A, the
bottom cover must be removed.
Table 5-1. Test Equipment Required
Type
Characteristics
Use
Recommended Model
Digital Voltmeter
Accuracy: ±0.004%
Precision dc voltage measurements HP Model 3455A or 3490A
Oscilloscope
Bandwidth: dc to 50MHz
Adjust zero output accuracy. Check
handshake cycle timing. CMOS logic
circuit troubleshooting.
HP Model 180C with 1803A
and 1821A piug-ins.
Logic Probe
Impedance: 250, Trigger
Thresh: 2.0V and 0.8V (nom)
Min. Pulse Width: lOnsec.
TTL logic circuit troubleshooting.
HP 10525T
TTL/CMOS
Logic Probe
TTL/CMOS logic circuit
trou bfeshooting
HP 545A
5-1