Tektronix 1720

Checks and Adjustments
1720/1721
5–13
o. Remove the precision high-frequency terminator from the RF Bridge.
p. Connect the male-to-male bnc adapter to the Device Under Test
connector on the RF Bridge.
q. Connect the Device Under Test connector on the RF Bridge to the
1720–Series CH-A INPUT. Terminate the CH-A loop-through with the
same precision high-frequency terminator used in step o.
r. Select CH-A INPUT.
s. Check – that the Reference Level Readout on the spectrum analyzer is
w40 dBm, with the instrument on and off.
t. Repeat parts q. through s. for each Input channel (CH-B and EXT REF).
u. Remove all cables and terminators from the 1720–Series.
12. Check Trace Rotation Range
REQUIREMENT – Range greater than ±1° from horizontal.
a. Connect the Function Generator output to pin 3 (+X) of the 1720/1721
rear-panel XY INPUT connector, using an alligator clip to bnc adapter.
Connect the red alligator clip to pin 3. See Figure 5-5.
b. Connect the black alligator clip to pins 1 and 5.
c. Set the Function Generator to produce a sinewave output.
d. Adjust the Function Generator amplitude for a displayed trace on the
horizontal axis that is greater than the width of the graticule compass
rose.
e. If necessary, use a small screwdriver and adjust the 1720/1721 vertical
positioning to place the trace on the horizontal axis.
f. Use a small screwdriver to adjust the 1720/1721 ROTATE from end to
end.