TM 11-6625-586-45
Table 6-4. External Modulation, Deviation and Distortion Check --Continued.
speaker. Connect step attenuator to output con-
Table 6-5. External Modulator Deviation Sensitivity
Check
nector of Z105. Set step attenuator for 0 db at-
External
tenuation. It is to be used as a 50-ohm load.
modulation
External
modulation
voltage limit
Frequency
b. Turn FUNCTION switch to FREQ CAL.
frequency
Deviation
(maximum)
c. Turn BAND switch to select band A.
10kHz
2 voltts rms
20
40kHz
d. With RF TUNING control to select a fre-
30kHz
quency of 20 MHz.
80
10kHz
2 volts rms
40kHz
30kHz
e. Fine tune around 20 MHz with RF TUNING
control to obtain a 4 kHz beat note as indicated
6-14. RF Frequency Drift Due to Attenuator
on frequency counter. Record this frequency for
Settings
reference.
f. Adjust LO-HI RF SET TO LINE control
to LO RF jack and electronic counter to speaker
for red line indication on IF UV RF SET TO
terminal. Check to ensure ground terminal of
LINE meter.
electronic counter is connected to ground side of
g. Set LO RF UV control to 10 KUV.
6-9
