TB 9-6625-127-24
am. Set TI FRQ to 1.00 MHz and adjust A1C204 (fig. 1) for a frequency counter
indication of 1.00 MHz ±0.05 MHz. (R)
an. Repeat steps al and am above until both specifications are achieved.
ao. Set TI FRQ to 2.99 MHz and connect TI OUTPUT to oscilloscope 1 input. Connect
TI TRIG OUTPUT to oscilloscope 2 input.
ap. Set oscilloscope sweep to 100 ns / div and vertical deflection for a convenient
displayed amplitude.
aq. Record amplitude of displayed signal.
ar. Set TI FRQ to 9.99 MHz and check that output amplitude decreased by 2% to 4%
from amplitude recorded in step aq above.
as. Set TI FRQ to 10 MHz. Connect TI TRIG OUTPUT back to frequency counter A
input and adjust A2R17 (fig. 2) for a frequency counter indication of 10.00 MHz ±0.03 MHz. (R)
at. Re-connect TI TRIG OUTPUT to oscilloscope 2 input.
au. Set TI FREQ to 2 MHz.
Use oscilloscope markers to mark current signal
amplitude.
av. Set TI FREQ to 50 MHz.
symmetrical signal as shown in figure 3 below, and a measured frequency of 50.0 MHz
±1.0 MHz. (Connect TI TRIG OUTPUT to frequency counter to measure frequency).
Figure 3. HF symmetry.
ax. Connect TI OUTPUT to spectrum analyzer input.
ay. Setup spectrum analyzer to display fundamental, at 0 dB, and at least first two
distortion. (R)
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