Atec Tektronix-1502 - Manual (Page 42)

TM 9-4935-601-14-3&P
Performance Check
21. Check that the jitter is not greater than 0.1 division (200 ps). See Fig. 4-2.
22. Change the MULTIPLIER control to X.1 and adjust the ZERO REF SET control to locate the pulse on
the graticule center. Check that the jitter is not greater than 0.2 division (40 ps). (If jitter is not correct, the
tunnel diode, CR1703, or Pulse Generator circuitry may be faulty, or the problem could be due to noise from
the Sweep Inverter or the Fast Ramp.)
23. Change the mp/DIV control to 50, and turn the POSITION control counterclockwise to display the top of
the trace on the graticule, then with the DISTANCE control set to 000 adjust the ZERO REF SET control to
locate the pulse on the reference graticule line.
24. Set the DISTANCE control to 500 and adjust the POSITION controls to center the trace on the
graticule, then return the DISTANCE dial to 000.
25. While viewing the trace, adjust the DISTANCE dial from 000 to 100. The trace aberrations must
remain within 1 division of the centerline ( 5% peak aberrations for the first 10 feet). See Fig. 4-3.
26. Change the mp/DIV control to 5, set the DISTANCE dial to 500, recenter the trace, then return the
DISTANCE dial to 100.
27. While viewing the trace, adjust the DISTANCE dial from 100 to 999. The trace aberrations must
remain within 1 division of the centerline ( 0.5% peak beyond 10 feet).
28. Return the DISTANCE dial to 100 and push the NOISE FILTER button in. While viewing the trace,
adjust the DISTANCE dial from 100 to 999. The trace aberrations will typically be less than was observed in
the previous step. If there is a problem with aberrations or noise, Sampling Gate diode CR1732, tunnel diode
CR1703, or Lo Freq Comp R1657 are likely causes.
29. Release the NOISE FILTER button, return the DISTANCE dial to 000, and set the mp/DIV control to
200.
30. Remove the 50
Ω
terminator from the CABLE connector. Install the GR to bnc adapter and the GR
short. Check that the reflected rise time of the pulse (fall time) is <0.7 divisions. (140 ps.)
The bnc shorted input is inductive and is not adequate for the reflected rise time (fall time) measurement.
Performance Checks-Option 5, Metric Version (Continue with Stop 59 for Standard Version)
31. Set the front panel controls as follows:
INTENSITY Fully cw
ZERO REF Fully cw
POSITION Midrange
mp/DIV 500
DISTANCE 000
NOISE FILTER Out
METRES/DIV 50
X1/X.1 X1
CABLE DIELECTRIC
SOLID POLY In
SOLID PTFE Out
Other Out
VAR Fully cw
Figure 4-2. Jitter Check. Figure 4-3. Aberration Check.
REV JUL 1982
4-4