TB 9-6625-2059-24
14. Oscilloscope Deviation and Frequency Error
a. Performance Check
(1) Position controls as listed in (a) through (d) below:
(a) GEN-RCVR switch to RCVR.
(b) FREQUENCY MHz switches to all zeroes. If, necessary, adjust ZERO
RCVR (front panel) adjust for 0 indication on FREQ ERROR meter.
(c) DEV-VERT V/DIV outer switch to 15 kHz.
(d) VERT control to center oscilloscope trace on horizontal center graticule line.
(2) Set FREQUENCY MHz switches to 000 010 0.
If oscilloscope trace is not
between -9.5 and -10.5 kHz, perform b (1) below.
NOTE
Trace will appear approximately 2 major divisions below
horizontal centerline.
(3) If FREQ ERROR meter does not indicate negative between 9.5 and 10.5 kHz
perform b (2) below.
(4) Position controls as listed in (a) through (d) below:
(a) FREQUENCY MHz switches to all zeroes.
(b) EXT DEV-VERT V/DIV outer switch to 6 kHz.
(c) FREQ ERROR meter switch to 5.
(d) VERT control to center oscilloscope trace on horizontal center graticule line.
(5) Set FREQUENCY MHz switches to 000 004 0. If oscilloscope trace is not
between -3.8 and -4.2 kHz, perform b (3) below. If FREQ ERROR meter does not indicate
negative 3.8 and 4.2 kHz, perform b (4) below.
(6) Position controls as listed in (a) through (d) below:
(a) FREQUENCY MHz switches to all zeroes.
(b) DEV-VERT V/DIV outer switch to 1.5 kHz.
(c) FREQ ERROR meter switch to 1.5.
(d) VERT position control to center oscilloscope trace on horizontal center
graticule line.
(7) Set FREQUENCY MHz switches to 000 001 0. If oscilloscope trace is not
between -0.9 and -1.1 kHz, perform b (3) below. If FREQ ERROR meter does not indicate
negative between 0.9 and 1.1 kHz, perform b (5) below.
(8) Set FREQUENCY MHz switches to 1255000.
(10) Adjust signal generator frequency for 125.500 MHz and amplitude for -70 dBm.
(11) Record frequency error indication of FREQ ERROR meter.