Giga-tronics GT 9000, Operation & Maintenance Manual

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4.1.8 Pulse Generator Verification
These steps verify that the pulse generator performs correctly.
PM Video Out Setup:
1. On the rear panel, connect PM VIDEO OUT to Channel 1 on the scope. On the front
panel, connect RF OUT through a detector to Channel 2 on the scope. This setup is to
verify that RF OUT is aligned with VIDEO OUT.
2.
Select an internal pulse at 4 GHz with 0 dBm. Then select a 5.0
µ
s pulse width at a rate
of 100 kHz and 0 ns delay.
3. Trigger scope on Channel 1. Ensure that the time delay between the PM VIDEO OUT
and RF OUT pulses is <10 ns. Verify that PM VIDEO OUT is a nominal 1 Vpp into 50
Ω
.
PM Sync Out Setup:
1. On the rear panel, connect PM SYNC OUT to Channel 1 on the scope and
PM VIDEO OUT to channel 2. This setup is to verify that SYNC OUT is aligned with
VIDEO OUT.
2.
Trigger scope on Channel 1. Ensure that SYNC OUT is 1 Vpp into 50
Ω
and that the
sync pulse width is 50 ns wide +5 ns.
3. Verify that PM VIDEO and SYNC OUT are aligned 5 ns.
Delay Test Setup:
1. Connect Input A on a Universal counter or equivalent to SYNC OUT and connect Input
B to VIDEO OUT.
2. Set the UUT for 2 seconds delay.
3. Set the counter to Time Interval (TI) A-B, and set Inputs A and B to 50 ohms. Use a
rising edge trigger, DC coupled, and a level of 0.5 V. This setup is to set level sensitivity.
4. Verify a 2 second delay +10 ms on the frequency counter.
5. If required, on A5-A1 adjust C32 for 2 second delay 10 ms.
Calibration and Testing
Manual No. 120AM00250, Rev C, September 1998
4-7