TB 9-6625-2076-35
Test instrument
Calculated ratio limits
DDM settings
Min
Max
0.093
1.60417
1.60756
0.155
2.26264
2.26797
0.200
2.99600
3.00400
(14) Set DDM to .046 and press FUNCTION/CONTROL T/F U/L D/R pushbutton.
(15) Repeat (10) through (13) except to calculate ratio divide value recorded in (10)
above by value recorded in (11) above.
b. Adjustments
(1) Alternately press TONE SELECT 90 Hz and 150 Hz pushbuttons (only one
TONE SELECT pushbutton on at a
time) and
adjust R7
(fig. 1b) until
voltage between the
two tones is within 50 V (R).
(2) Press TONE SELECT 150 Hz pushbutton (all other TONE SELECT
pushbuttons off). Adjust R4 (fig. 1b) for a 1 V rms indication on digital multimeter (R).
(3) Press TONE SELECT 90 Hz pushbutton. If digital multimeter does not
indicate 1 V rms, repeat (1) and (2) above until correct indications are obtained.
(4) Adjust R5 (fig. 1b) for a 1.500 V rms indication on digital multimeter (R).
a. Performance Check
(1) Connect digital multimeter to TI COMP output (rear panel).
(2) Press FUNCTION/CONTROL STD pushbutton and enter a frequency of
335.00 MHz into TI.
(3) Press TONE SELECT 90 Hz pushbutton (all other TONE SELECT
pushbuttons off). Record digital multimeter indication.
(4) Press TONE SELECT 150 Hz pushbutton (all other TONE SELECT
pushbuttons off). Record digital multimeter indication.
(5) Divide the measured value of one tone by the other to determine the voltage
ratio. Calculated ratio will be between 0.99975 and 1.00025.
(6) Connect digital multimeter to TI DEMOD output (rear panel).
(7) Repeat (3) through (5) above. Calculated ratio will be between 0.99745 and
1.00255.
(8) Connect equipment as shown in figure 3. Set decade resistor to 47 kΩ.
(9) Press TONE SELECT 90 Hz pushbutton (all other TONE SELECT
pushbuttons off) and enter a DDM setting of 0.045 into TI. Record digital multimeter
indication.
12 CHANGE 2
PIN: 054298-002