User`s guide

1-110
Making Measurements
Using Test Sequencing
Changing the switch state back to the standard mode requires a 7 to be entered in the
“TESTSET I/O FWD.”
Pin 1 on the external switch must be grounded. It can be grounded to:
• the analyzer's chassis
• the front panel binder post
• the outer shell of the TEST SET-I/O INTERCONNECT connector
• a ground pin on the TEST SET-I/O INTERCONNECT connector (pin 7, 12 or 18). Refer
to Figure 1-79.
Pin C (common) on the external switch (8762B Option T24) must be connected to the test
set interface pin 14 (+22 volt line). Refer to Figure 1-79.
Pin 2 on the external switch, connects to pin 22 (TTL 1) on the test set interface.
The TTL I/O can control both of the external RF switches. Both must be cascaded in
parallel together. Changing the TTL I/O FWD from 7 to 6 will change the external RF
switch state. This changes the measurement capability from the network analyzer to the
external test measurement device. The TTL I/O FWD when changed from 7 to 6 will
reverse the process.
Table 1-5 Test Set Interconnect Pin Designation
Pin Number Pin Description
Pin 1 No Connection (NC)
Pin 2
Sweep delay: holds off sweeps until test set has finished sweeping (85046A/B and 85047B
only)
Pin 3
Same as Test Sequence (TTL OUT) output BNC connector
Pin 4
NC
Pin 5
NC
Pin 6 NC
Pin 7
Ground
Pin 8
Hi-forward/Low-reverse. Follows the test port indicator.
Pin 9
NC
Pin 10 Lstarttrig: Not used. Do not connect anything to this pin.
Pin 11 TESTSET I/O Bit 2 (most significant bit). +5 V when TESTSET I/O has values of 4, 5, 6, or
7. Otherwise, bit is TTL low.
Pin 12
Ground
Pin 13
NC
Pin 14
+22 Volts
Pin 15
NC