GE ApexPro TT, Technical Manual

Page: 81 / 192

Maintenance
2001989-351A ApexPro™ 4-19
4. Connect the external 10 MHz reference to the EXT TRIG IN/EXT REF IN .
NOTE
The external reference must be accurate to 0.0083ppm. Ensure that you
allow the external reference to warm up (See the device operators manual).
5. Set the analyzer for external 10MHz reference mode.
a. Press SETUP .
b. Press F3 - HARDWARE SETUP .
c. Select BNC I/O MODE and press ENTER .
d. Select EXT REF IN and press ENTER .
6. Ensure the preamplifier is on.
a. Press SETUP .
b. Press F3 - HARDWARE SETUP .
c. Select PREAMP and press ENTER .
d. Select ON and press ENTER .
7. Set the center frequency to match the target frequency of the receiver subsystem
being tested.
a. Press FREQ .
b. Type the target frequency, press the correct units button and press ENTER .
8. Set the reference amplitude to -60 dBm.
a. Press AMPT .
b. Type -60 , press dBm and press ENTER .
9. Set the span to 1 kHz.
a. Press SPAN .
b. Type 1 , press kHz and press ENTER .
10. Set the resolution bandwidth to 100 Hz.
a. Press BW .
b. Press F1 - MANUAL RES BW .
c. Type 100 , press Hz and press Enter .
NOTE
Ensure that the antenna is located as close to the back of the receiver as
possible. Depending on the antenna used, the signal will be very small
(–100 dBm or smaller). When positioning the antenna, do not move it
too quickly as the analyzer is doing a three cycle average and the peak
will build. If you do not see a signal, change the center frequency up or
down by 1 kHz up to 4 kHz (signal should not be outside of this range).
Ensure that the resolution bandwidth does not change while doing this.