2
6888882V04
Introduction
This manual covers the installation and operation of the MICOM RM1200 1 kW linear high-power RF
amplifier unit, FLN3175. RM1200 uses the MICOM RM125 or RM125R, part of the MICOM-3 line of
HF-SSB radio sets, as exciter and controller to implement a complete 1 kW transceiver.
The manual covers only procedures specific to the MICOM RM1200. For procedures related to the
RM125 and RM125R, refer to the “RM125/RM125R Owner’s Guide”, Publication 6888882V02. The
other procedures, which are common to the whole MICOM-3 product line, are described in the
“Owner’s Guide, MICOM-3F/3T/3R HF-SSB Transceivers”, Publication 6886867J01, and in other
MICOM-3 Supplements that cover optional features applicable to your radio set.
Note
If you are using a different type of exciter/controller, use its vendor’s manual
instead of the MICOM-3 publications.
1
kW System Description
The RM1200 1 kW power amplifier, FLN3175, expands the MICOM-3 product line by offering
higher transmit power (up to 1 kW, PEP and average), and thus longer reach and improved
communications under bad propagation conditions and/or strong interference.
RM1200 consists of two units intended for rack mounting, together with the exciter unit: 1 kW RF
linear power amplifier and AC-powered PS unit. The equipment is well suited for base station
applications, and can be directly connected to a wide range of broadband or tuned antennas,
including whip, dipole, traveling wave, delta, and semi-delta antennas.
Upon power-up, the RM1200 uses a low-level RF pilot signal from the exciter to automatically detect
the incoming frequency and select the optimum harmonic filter band in accordance with the
operating frequency. The frequency detection and filter switching is quite rapid, a capability needed
for ALE and adaptive communication modes.
The RM1200 is optimized for operation in conjunction with the RM125 or RM125R radio set as
exciter and controller, using a dedicated communication interface and a flexible handshaking
protocol (to use these capabilities, order the special interface cable kit, option G156, for connecting
the 1 kW amplifier to the RM125/RM125R). The RM125/RM125R controls the 1 kW amplifier
operation, enables the operator to select the nominal transmit power, and the 1 kW amplifier
provides ALC feedback to adjust the RM125/RM125R drive power to the optimum level.
Caution
Before putting a new RM1200 into operation, it is necessary to calibrate
the system to obtain the correct transmit power (this calibration must
also be performed after either the exciter or the RM1200 is replaced).
Calibration instructions for the recommended exciter, RM125/RM125R,
appear in the Publication 2072-09538-00, “Radio Service Software (RSS)
User’s Guide” for RSS V3.0 and higher.
Although optimized for operation with the RM125/RM125R, RM1200 can be used with any HF-SSB
driver capable of providing the required drive power (approx. 40W), and appropriate interfacing.
Contact the manufacturer for details on the RM1200 interfacing requirements.
