Residual Responses

TM 11-6625-2781-14&P-2

Section IV

PERFORMANCE TESTS (cont'd)

4-29. Residual Responses (cont'd)

2. Terminate the RF INPUT jack in 50 ohms.

3. Observe the display as the analyzer scans from 10

to 110 MHz. The average noise level should be less

than -110 dBm and no residual responses should

occur. Figure 4-13 represents a scan with no

residual response, and with the average noise level

indicated.

Residual Responses 10-110 MHz:

<-110 dBm

4. To check the analyzer from 1 MHz to 10 MHz, make

the following control settings:

FREQUENCY ................................ ............. 5 MHz

Figure 4-13. Residual Response Test:

SCAN WIDTH PER DIVISION .................... 1 MHz

10 to 110 MHz CRT Display

SCAN TIME PER DIVISION ............. 2 SECONDS

5. Observe the display for residual responses:

Residual Responses 1-10 MHz:

<-110 dBm

6. To check the analyzer from 200 kHz to 1 MHz, make the following control settings:

FREQUENCY ................................ ................................ ................................ ........ Local Oscillator signal appears at

left hand edge of graticule

SCAN WIDTH PER DIVISION ................................ ................................ ................................ ..................... 0 1 MHz

BANDWIDTH ................................ ................................ ................................ ................................ ................ 0 3 kHz

SCAN TIME PER DIVISION ................................ ................................ ................................ ................. 5 SECONDS

7. Observe the display for residual responses over the last 8 horizontal divisions:

Residual Responses 1-10 MHz:

<-110 dBm

8. To check the analyzer from 20 to 200 kHz, make the following control settings:

RANGE - MHz ................................ ................................ ................................ ................................ ........... 0-11 MHz

FREQUENCY ................................ ................................ ....... Local Oscillator signal appears at left hand of graticule

SCAN WIDTH PER DIVISION ................................ ................................ ................................ ....................... 20 kHz

BANDWIDTH 0 ................................ ................................ ................................ ................................ .............. 01 kHz

BANDWIDTH ................................ ................................ ................................ ................................ ................ 0 1 kHz

SCAN TIME PER DIVISION ................................ ................................ ................................ ................. 5 SECONDS

LOG REF LEVEL ................................ ................................ ................................ ................................ ......... -50 dBm

9. Observe the display for residual responses over the last nine horizontal divisions:

Residual Responses 1-10 MHz:

<-95 dBm

4-19