TB 9-4931-488-24
(15) Disconnect true rms voltmeter from A11TP5 (fig. 3) and connect to A11TP3
(FM OUT, fig. 3). True rms voltmeter should indicate within 0.005 V ac of value recorded
in technique (14) above.
(16) While observing true rms voltmeter, slowly vary modulation frequency from 20 Hz
to 100 kHz. True rms voltmeter should indicate within 0.025 V ac of value recorded in
technique (14) above.
(17) Repeat technique of (16) for 100 to 600 kHz. True rms voltmeter should indicate
within 0.050 V ac of value recorded in technique (14) above.
(18) Set MODULATION FREQUENCY range
switch
to
and
adjust
x3k
MODULATION FREQUENCY vernier dial to 20.
(19) Disconnect frequency counter and true rms voltmeter from TI. Connect true rms
voltmeter to AM OUTPUT, using 600 Ω termination. Adjust A11R40 (AUDIO OUTPUT
LEVEL, fig. 3) for 3.10 0.03 V ac true rms voltmeter indication.
(20) Set RF OFF/ON switch to OFF. Disconnect equipment setup.
15. AM Sensitivity, Accuracy, and Distortion (All Models Except Those Containing
Option 004)
a. Performance Check
(2) Position controls as listed in (a) through (k) below.
(a) COUNTER MODE INT EXT pushbutton pressed.
(b) COUNTER MODE EXPAND X10 and X100 pushbuttons released.
(c) COUNTER MODE LOCK ON pushbutton released.
(d) AM X10% pushbutton pressed.
(e) AM switch to DC.
(f) AM control fully cw.
(g) FM switch to OFF.
(h) RANGE MHz switch to 512 - 256.
(i) FREQUENCY TUNE control for a FREQUENCY MHz display indication of
500 MHz.
(j) OUTPUT LEVEL switch to +10 dBm and vernier control(s) fully cw.
(k) RF OFF/ON switch to ON.