Tektronix RFM150, Instruction Manual, Page: 145 / 278

Performance Check
RFM 150 Instruction Manual 5–7
b. Apply a 10 MHz sinusoidal signal at a characterized
amplitude of +38.7 dBmV (in 75
W
) to the RF input.
c. Record the RFM 150 reading in your copy of Table 5–1.
Verify that this value is within 1 dB of the power meter
reading.
d. Repeat for frequencies of 110, 210, 310, 410, 510, 610, 710,
810, 910 and 1000 MHz.
6. Verify hum measurement accuracy as follows:
a. Use the following key sequence to tune the RFM 150 to
511.25 MHz: [5] [1] [1] [.] [2] [5] [MHz].
b. Input a +38.7 dBmV, 511.25 MHz sinusoidal signal.
c. Use the following key sequence to select hum measurement
mode: [MEAS] [F2].
d. Verify that the residual hum reading is less than 0.5%. Record
the RFM 150 reading in your copy of Table 5–1.
e. Apply 2.5% AM modulation at a rate of either 50, 60, 100, or
120 Hz.
NOTE
. If the AM modulation rate cannot be set to these values on the
signal generator, use an external modulation source and adjust the
amplitude according to that manufacturer’s setup procedure.
f. Verify that the displayed hum reading is 5
±
1%. Record the
RFM 150 reading in your copy of Table 5–1.
NOTE
. The RFM 150 Hum reading is the ratio of peak-to-peak AM
modulation to carrier level, per the NCTA standard. The displayed
result will be twice the percent modulation setting on the generator.
7. Verify FM deviation measurement accuracy as follows:
a. With the instrument still tuned to 511.25 MHz, apply a
+38.7 dBmV, 515.75 MHz sinusoidal signal with 12 kHz of
deviation at a rate between 20 Hz and 7.5 kHz.
Performance Check
RFM 150 Instruction Manual 5–7
b. Apply a 10 MHz sinusoidal signal at a characterized
amplitude of +38.7 dBmV (in 75
W
) to the RF input.
c. Record the RFM 150 reading in your copy of Table 5–1.
Verify that this value is within 1 dB of the power meter
reading.
d. Repeat for frequencies of 110, 210, 310, 410, 510, 610, 710,
810, 910 and 1000 MHz.
6. Verify hum measurement accuracy as follows:
a. Use the following key sequence to tune the RFM 150 to
511.25 MHz: [5] [1] [1] [.] [2] [5] [MHz].
b. Input a +38.7 dBmV, 511.25 MHz sinusoidal signal.
c. Use the following key sequence to select hum measurement
mode: [MEAS] [F2].
d. Verify that the residual hum reading is less than 0.5%. Record
the RFM 150 reading in your copy of Table 5–1.
e. Apply 2.5% AM modulation at a rate of either 50, 60, 100, or
120 Hz.
NOTE
. If the AM modulation rate cannot be set to these values on the
signal generator, use an external modulation source and adjust the
amplitude according to that manufacturer’s setup procedure.
f. Verify that the displayed hum reading is 5
±
1%. Record the
RFM 150 reading in your copy of Table 5–1.
NOTE
. The RFM 150 Hum reading is the ratio of peak-to-peak AM
modulation to carrier level, per the NCTA standard. The displayed
result will be twice the percent modulation setting on the generator.
7. Verify FM deviation measurement accuracy as follows:
a. With the instrument still tuned to 511.25 MHz, apply a
+38.7 dBmV, 515.75 MHz sinusoidal signal with 12 kHz of
deviation at a rate between 20 Hz and 7.5 kHz.