WIDE BANDWIDTH MEASUREMENT

TM 11-5820-918-13

5-31. WIDE BANDWIDTH MEASUREMENT. Perform this measurement in accordance with

the following procedure:

Turn off the TCS-4B transmitter and disconnect the antenna.

b. On the 1024, place the DIRECT/DIPLEX switch in the DIPLEX position. Place

the .1 PWR/FULL PWR switch in the .1 PWR position.

CAUTION

This test must be performed with the DIRECT/DIPLEX switch in the

DIPLEX position and the .1 PWR/FULL PWR switch in the .1 PWR

position. If these switch settings are not observed, severe damage

to the test equipment will occur.

c. Set up the equipment as shown in figure 5-9. The spectrum analyzer should

be set to 0-100 MHz scan-width range and a full scale sensitivity of 0 dBm with input

attenuator set to 30 dB. Set the 1024 to 2-30 MHz range.

d. Turn on the TCS-4B transmitter. With the 1024 MODE switch in MAN position,

press RESET, then press START. Throughout the sweep all harmonics should be

at least 60 dB below the fundamental and all spurs should be at least 50 dB below the

fundamental.

e. If harmonics are not at least 60 dB, and/or spurs not at least 50 dB below the

fundamental, replace the 4011 filter set, 3A1A1 and/or filter decode 3A2A2. Repeat

the measurement.

f. If harmonics and/or spurs persist, re-install original filter set or filter decode

and replace the sweep synthesizer, 1A1, in the 1024. Repeat the measurement.

5-32. NARROW BANDWIDTH MEASUREMENT. Perform this measurement in accordance

with the following procedure:

Repeat steps a and b of paragraph 5-31.

b. Make the following settings on the spectrum analyzer.

(1) Input Attenuator: 30 dB

(2) Bandwidth: 10 kHz

(3) Scan Width: 100 kHz/div.

(4) Scan Time: 10 ms/div.

(5) Video Filter: 10 kHz

(6) Range: 0-110 MHz

(7) Center Frequency: 2 MHz