120 10503-201 PRELIMINARY
T-96S Technical Manual
13
Table 6: Tests and Adjustments
half channel
units (12.5 kHz & 15 Khz models)
STEP
ACTION
EXPECTED
RESULTS at
25
°°°°
C
MEASURE
WITH
IF NOT?
1
Output Power
Press
PTT Channel x
5 watts
1
+10%, -20%
Service monitor
set to read
power
Check T96RSS maximum
power output setting: must
be set to 255 (means 5W)
Refer to factory tech
support.
2
Frequency Error
Press
PTT Channel x
±300 Hz
Service monitor
set to read fre-
quency error
Open the uniit (see 3.4.4)
Adjust the Frequency Ad-
just control on the TCXO
2
3
Deviation
Press
PTT Channel x
±3.0 kHz
3
+5%, -10%
Service monitor
set to read de-
viation with mid
(15 - 30 kHz) IF
filter.
Using T96HRSS, adjust TX
deviation with the up/down
arrows.
4
Set the service monitor to generate a -80 dBm signal on the selected receive frequency. The
signal should be modulated with a 1.0 kHz tone.
5
Demodulated Audio
For 1200 - 4800 b/s set
generator deviation to
±2.0 kHz.
2.0 ±0.2 Vpp
Oscilloscope
connected to
pin 4 of the data
I/O connector.
4
Using T96HRSS, adjust
receive audio level with the
up/down arrows.
6
12 dB SINAD
Set deviation to 1.5kHz.
Set IF filter to mid (15-
30 kHz), no audio filter.
≤
0.5
µ
V
5
Service monitor
set for SINAD.
Connect to pin
4 of the data I/O
connector
4
.
Refer to factory technical
support.
7
Distortion
Set deviation to 1.5kHz.
Set IF filter to mid (15-
30 kHz), no audio filter.
< 3%
Service monitor
set for Distor-
tion. Connect to
pin 4 of the data
I/O connector
4
.
Refer to factory technical
support.
1 (unless you have set a lower value). Note that readings less than 5 watts may be due to losses in the cables used for
testing. Check also your wattmeter frequency calibration curve. Do not be too ready to condemn the transmitter.
2
The TCXO adjustment is accessible through the hole next to the DIP switch on the logic board.
3
The unit is automatically set to 9600 b/s (Bt.3) for this procedure.
This T96H model has not been designed to op-
erate at 19200 b/s using half channel radios.
If the unit is later used at 4800 b/s (Bt.5), the deviation will be auto-
matically set to ±2.0 kHz.
4
Pin 4 is accessible by removing the cable connector hood. If you anticipate frequent need for access to this pin, sol-
der a short insulated lead to that pin on the cable connector and replace the hood. (The same signal is available at
TP1 on the logic board if the unit is open).
5
If a psophometrically weighted filter is available on the service monitor, use 0.35
µ
V.