TM
FOR UNITS WITH SERIAL
NUMBERS EXCEEDING 110
(PCB REVISION 0198 ONWARDS)
11-38-0000
Synthesized UHF
Transceiver
User’s Handbook
Sea Air and Land Communications Ltd, Christchurch, New Zealand
11-38-0000 SYNTHESIZED TRANSCEIVER OPERATOR’S MANUAL Issue 1138UA
Manual applies to 11-38s with serial numbers greater than 110 (PCB issue 01/98 onwards) Page 1
11-38 SYNTHESIZED TRANSCEIVER
OPERATOR'S MANUAL
1.0 DESCRIPTION: The Salcom 11-38 is a 1.2w UHF narrow band FM Transceiver
using ±5kHz deviation on the UHF 25kHz channel spaced bands, 406-430MHz and
450-475MHz. In addition a version using 12.5kHz channel spacing in the 450475MHz band (± 2.5kHz deviation) is available. The transceiver design is based
upon the separate 11-23 receiver and 11-24 transmitter and therefore has many
similarities. There are also many mechanical similarities to the crystal controlled
TR460 (10-84-0000) transceiver.
The 11-38 is supplied tuned to the requested frequency. Up to 16 independent
receive and transmit frequencies may be pre-programmed and selected by internal
DIP switches. The transmitter power output may also be internally adjusted to
between 50mW to approximately 1.2 Watts output.
2.0 OPTIONS: Special options are available and can be ordered with the 11-38 or
retro-fitted by your supplier:
! 600O balanced input when T101 fitted.
3.0 SETUP INSTRUCTIONS
3,I Deviation on data source: When transmitting a constant level tone from
a modem or tone encoder use AF1 input (Comms connector pin 3). Monitor
the demodulated waveform on a modulation meter and set the line level
control AF1 (RV301) so that a clean sine wave is visible. Adjust the
deviation control "MOD" (RV304) for ±4kHz deviation with the modulating
source (i.e.modem idle tone), or ±2kHz for 12.5kHz bandwidth.
3.2 Deviation on speech source: If an uncompressed varying level
modulation (i.e. speech) is being transmitted, then the AF2 input (comms
connector pin 13) can be used. RV303 (MIC) sets the sensitivity of the
microphone input and should initially be set to about 9 o’clock.
Set RV302 (AF2) for minimum distortion of the envelope when transmitting
maximum audio. Typically adjust this until clipping of the output waveform
is apparent and then reduce RV302 (AF2) until the signal is clean. Adjust
the deviation control (RV304) for the correct transmit deviation (± 3kHz for
25kHz systems and no greater than ± 2kHz for 12.5kHz bandwidth
systems. The microphone level at the lowest input level can be increased
by adjusting RV303 (MIC).
11-38-0000 SYNTHESIZED TRANSCEIVER OPERATOR’S MANUAL Issue 1138UA 11-38-0000 SYNTHESIZED TRANSCEIVER OPERATOR’S MANUAL Issue 1138UA
Manual applies to 11-38s with serial numbers greater than 110 (PCB issue 01/98 onwards) Page 2 Manual applies to 11-38s with serial numbers greater than 110 (PCB issue 01/98 onwards) Page 3
Pre-emphasis/de-emphasis: By default the unit is supplied with a bridge
header inserted in B301. In this mode the settings are “flat” (no mic preemphasis and no receiver de-emphasis).
If required, mic pre-emphasis is enabled by removing the 2 pin bridge
header from B301 and placing it onto B102. This automatically puts the
receiver into the de-emphasis mode.
Busy output: A " busy" logic signal level of approximately 8 volts is
available at pin 7 of the D15 socket. The phase of the signal can be
reversed by transferring the bridge header at JU101 between the 3 pin
connector.
Line Transformer: Provision is made for an optional fitting of line
transformer T101. If it is desired to receive and transmit audio via the
transformer then B101 (pcb bridge) should be shorted. This will then route
the transmit audio to the modulator data input (uncompressed). If it is
desired to run to the compressor input (with optional pre-emphasis) then
do not blob B101 as it is necessary to hardwire a connection from B101
(T101 side) directly to pin 13 of SK101 (D15 socket)
4.0 INSTALLATION: Use a screwdriver to connect the power socket, and a soldering
iron to connect the D15 communications plug and the aerial, are required for the
installation procedure.
4.1 Connections:
AERIAL SOCKET
Connects to the aerial (half wave dipole or yagi) via a BNC plug and 50O coaxial
cable.
POWER PLUG
Connects to +12V supply and ground. The polarity is marked on the 11-38 case
COMMUNICATIONS SOCKET
Pin 1 Earth connections.
Pin 2 Receiver audio output (16O)
Pin 3 Transmitter audio data input 10K (AF1, RV301)
Pin 4 Received signal strength (RSSI) -117dB to -47dBm, 47K
Pin 5 PTT. Earth to initiate a transmission.
Pin 6 TXD programming data, RS232 format, 0 to 5V logic
Pin 7 Busy output from squelch circuit, 0-8/12V. Set jumper JU101 for phase
reversal
Pin 8
Pin 15
+12V supply for auxiliary circuits
Pin 9
Pin 10
No connection
Pin 11 600O balanced receiver output and transmit input (with B101 bridged to
Pin 12 link compressor input AF2).
Pin 13 Transmit audio compressor input 10K - (Mic, RV303 & AF2, RV302
Pin 14 RXD programming data, 0-5V logic.
5.0 OUTPUT: The transmitter can be operated continuously provided that the supply
voltage is limited to 13.5 volts. Also it is critical that the aerial is OK and the VSWR
must be below 2.0
6.0 OPERATING REQUIREMENTS:
! Supply voltage: +13.5V (12V nominal).
! Operating temperature range: -10 C to +60 C.
o o
! Mount in a dry position away from loud noise or vibration.
7.0 LED INDICATORS: Three indicator LED's are visible on the top of the case.
(I) Green Power LED shows power is present at the 11-38.
(2) Amber (yellow) lights when the 11-38 is receiving or the Squelch is open..
(3) Red TX LED lights when the 11-38 is in lock and transmitting.
8.0 REPROGRAMMING: The 11-38 can be re-programmed by a supplier with the
appropriate programming facilities to another frequency in the same band.
9.0 MOUNTING: Mount the case using the two holes provided in the lid and clip the
11-24 into position on the lid. Secure with the two self tappers to make positive
electrical contact between the case and lid and prevent RF recirculation.
10.0 WARRANTY: Our Products are warranted for a period of 12 months from date
of purchase against faulty materials and workmanship. Should any fault occur
the unit should be returned to the Vendor, freight pre-paid. Please include a
brief description of the fault to assist with prompt return. Any unauthorized
alterations or repairs will invalidate the warranty.
Loading...