Acom 1200S - OPERATION; RX;TX and OPERATE;STANDBY Modes

User's Manual | ACOM 1200S | 1.8-54 MHz Linear Power Amplifier
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| S e c t i o n OPERATION
August 2021
4. OPERATION
4.1. Change of Modes RX/TX and OPERATE/STANDBY; AUTO OPERATE User Setting
a) STANDBY mode
In STANDBY mode, as well as when the amplifier is not powered, receiving and transmitting (no more than
200 W) with the transceiver is done via RF bypass between RF INPUT and RF OUTPUT of the amplifier. In
STANDBY, the transceiver's RF power is not amplified, the control KEY-IN input does not affect the
operation, and the KEY-OUT output (see Section 2.4.c) KEY-OUT socket) follows the KEY-IN input
unconditionally.
b) OPERATE mode
In OPERATE mode the receive-transmit (RX/TX) direction is controlled by the KEY-IN input:
• At open KEY-IN (OPERATE/RX mode), the transceiver receives the signals from the antenna
through the same RF by-pass path between RF INPUT and RF OUTPUT as with amplifier
turned off or in STANDBY mode;
• At grounded KEY-IN ((OPERATE/TX mode) the RF drive is amplified and fed to the antenna
through the RF OUTPUT connector.
In order to provide time for the relays to switch safely from receive to transmit, the
transceiver should provide a dead time, i.e., must "notify" the amplifier in due time by
grounding the control KEY-IN input not later than 10 ms before feeding drive power
toward the amplifier RF input. Otherwise, the protection system will read "HOT
SWITCHING ATTEMPT" and will trip off.
In OPERATE mode the KEY-OUT output (see Section 2.4.c) KEY-OUT socket) follows the KEY-IN input only
after all conditions for safe transmission have been found good by the amplifier control unit. When used,
the KEY-OUT output duly disables transmission while the amplifier is not ready.
The two modes OPERATE and STANDBY may be changed:
• Manually (locally) - by pressing the OPR/STB button alternatively (see Figure 3-2 Basic screen
without ACOM 04AT antenna tuner assigned, Pos. (1));
• Automatically at a SOFT FAULT protection trip - when the AUTO OPERATE user setting is
activated (see Section 4.1.c) AUTO OPERATE user settings).
Access to the OPERATE mode can be locked in the AMP SERVICE menu, the OPERATE
ACCESS user setting (see Section 5.4 Menu USER PREFERENCES and 5.4.e) OPERATE ACCESS).