TB 9-6625-1914-24
NOTE
35 dB below fundamental level. Harmonic distortion will occur
at multiples of 9.950 and 10 MHz. Care must be taken not to
confuse harmonic distortion produced by the source with
intermodulation distortion produced by the input mixer.
(8) Repeat technique of (7) above for third-order intermodulation products at TI
frequencies of 10.050, 9.900, 29.950, and 29.900 MHz.
b. Adjustments. No adjustments can be made.
31. Local Oscillator Stability
a. Performance Check
(1) Connect signal generator RF output to TI RF INPUT.
(2) Position TI controls as listed in (a) through (e) below:
(a) FREQUENCY control to 100 MHz.
(b) BANDWIDTH switch to 10 kHz.
(c) SCAN WIDTH (red) switch to PER DIVISION.
(d) SCAN WIDTH PER DIVISION switch to 20 kHz.
(e) TUNING STABILIZER switch to OFF.
(3) Set IF plug-in SCAN TIME PER DIVISION switch to 2 ms and LOG/LINEAR
switch to LINEAR.
(4) Adjust signal generator output for 100 MHz CW at -30 dBm.
(5) Adjust LINEAR SENSITIVITY control and LINEAR SENSITIVITY (LOG
REF LEVEL vernier) vernier control as necessary to obtain a full 8-division display.
(6) Adjust FREQUENCY and FREQUENCY FINE TUNE controls as necessary to
center display.
(7) Readjust FREQUENCY controls until upward slope of signal pip intersects
CENTER graticule line one division from top graticule line as shown in figure 14. Note
where slope of display intersects center horizontal graticule line and record horizontal
displacement (fig. 14).