TB 9-4931-488-35
(8) Disconnect multimeter from A26A2TP1 (fig. 2). Set multimeter to measure dc
voltage and connect to AM OUT A26A2TP3 (fig. 2). Record multimeter indication (should
be 2.0 0.1 V dc).
(9) Multiply value recorded in (8) above by 0.3536. Set multimeter to measure ac
voltage. Adjust % AM A26A2R19 (fig. 2) until multimeter indicates within 0.001 V ac of
value computed above (R).
(10) Disconnect multimeter from A26A2TP3 (fig. 2). Set multimeter to measure dc
voltage and connect to DEMOD OUT. Adjust A26A8R10 (fig. 2) for a 1.414 0.001-V dc
multimeter indication (R).
dc multimeter indication (R).
(12) Set multimeter to measure ac voltage. Adjust A26A8R8 (fig. 2) for a 2.500 0.001
V ac multimeter indication (R).
(13) Return A26A8S1 switch (fig. 2) to position noted in a (18) above, provided a (18)
was performed.
(14) Connect equipment as shown in figure 6 except do not connect the true RMS
(15) Set measuring receiver to measure AM with peak + detector. Set high-pass filter
to 50 Hz and low-pass filter to 15 kHz.
(16) Press measuring receiver AUTOMATIC OPERATION and FREQ MHz keys.
(17) Record multimeter dc indication as Voff.
(18) Adjust audio analyzer controls for a 120-Hz, 600 Ω, 0.459 V output.
(19) Connect the measuring receiver sensor module to the TI RF OUT.
(20) Press AM X10% pushbutton and adjust AM vernier control fully cw.
(21) Adjust the audio analyzer output for a TI meter indication of 50%. Press 6.2 and
SPCL keys on measuring receiver.
(22) Record multimeter dc indication as Vdc.
(23) Calculate the AC component (Vac) using the formula. Round the calculated
value to 3 digits and record as Vac.
Vac = absolute value of (.5*( Vdc - Voff)/1.414)
(24) Set multimeter to measure ac voltage and adjust the audio analyzer output for a
multimeter indication as close as possible to the Vac value recorded in (23) above.
(25) Disconnect the multimeter from measuring receiver and connect it to TI
DEMOD OUT.
(26) Adjust A26A8R8 (fig. 2) for a multimeter indication of 2.5 0.005 Vrms.
(27) Disconnect the multimeter from the TI and connect to measuring receiver rear
panel OUTPUT AM.
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