Table 5. Normal Frequency Response

TB-9-6625-1947-35 Test Oscillator Hewlett-Packard Models 654A Manual
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TB 9-6625-1947-35

(13) Adjust calibrator to -0.5 percent of value recorded in (11) above. Record

multimeter indication as R4.

(14) Disconnect calibrator from thermal converter and connect thermal converter to

TI UNBAL output. Set FREQUENCY RANGE switch to X1M and FREQUENCY dial to 10.

(15) Adjust AMPLITUDE control for a 0 dBm indication on TI meter. If multimeter

does not indicate within limits of R3 and R4, perform b (11) through (13) below.

(16) Repeat technique of (14) and (15) above for FREQUENCY RANGE switch and

FREQUENCY dial settings listed in table 5. If multimeter does not indicate within limits

of R3 and R4, perform b (11) through (13) below.

Table 5. Normal Frequency Response

Test instrument

FREQUENCY RANGE

FREQUENCY

switch settings

dial settings

X1M

X100K

X10K

X1K

X100

X10

b. Adjustments

(1) Rotate A3R18 (fig. 2) fully cw.

(2) Adjust A3R7 (fig. 2) until AMPLITUDE control has sufficient range to exceed

maximum meter deflection at both ends of meter scale.

(3) Adjust AMPLITUDE control for a -1 dBm indication on TI meter. Record

multimeter indication as R2.

(4) Multiply R2 by 1.259 and record as R4.

(5) Adjust AMPLITUDE control for value of R4 on multimeter.

(6) Adjust A3R18 (fig. 2) for a +1.0 dBm indication on TI meter

(7) Adjust AMPLITUDE control for a 0.7071 V rms indication on multimeter.

(8) Adjust A3R7 (fig. 2) for a 0 dBm indication on TI meter (R).

(9) Rotate AMPLITUDE control fully cw.

(10) Adjust A3R20 (fig. 2) for a 0.80 V indication on multimeter (R).

(11) Adjust AMPLITUDE control for a 0 dBm indication on TI meter.

(12) Adjust A2C43 (fig. 1) for R2 value recorded in 9 a (9) above (R).

(13) Repeat 9 a (14) above.