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Fig. 2-1 Rear panel connections
c) KEY-OUT jack - transmit-enabling control output from amplifier to the transceiver.
The KEY-OUT jack on the rear panel provides an additional control signal from amplifier toward transceiver. It
can be used for improving reliability of the receive/transmit (RX/TX) switching.
When the amplifier is not powered up, KEY-OUT is connected internally to KEY-IN through the contacts of a
relay inside the amplifier, thus always enabling transceiver transmission. Also, in Stand-by mode KEY OUT
unconditionally follows the state of the KEY-IN input. When in Operate mode however, KEY-OUT follows KEY- IN
only when all conditions for safe transmission have been found OK by the amplifier control circuit. At detection of
any risk, transmission is quickly disabled by means of opening the KEY-OUT circuit constrainedly.
C A U T I O N
KEY-OUT is a low-powered output, this is why make sure that the signal
voltage coming to it from the respective transceiver connection does not
exceed 50VDC (open circuit) and that its closed-circuit current is below
20mA.
If your transceiver has a suitable input, which disables transmission unless it is grounded externally, we
recommend that you connect it to the KEY-OUT jack of the amplifier. Use shielded cable terminated with
а
standard “RCA PHONO” jack plug.
The manufacturers of transceivers give different names to this transceiver input, for example: TX-INHIBIT,
MUTE, LINEAR, and others. Check the manual of your transceiver. Approach your dealer for details. If your
transceiver has no such input, do not worry – ACOM 600S will operate normally without it as well – then KEY-
OUT jack can remain not connected.
d) RF INPUT – should be connected to the antenna input/output of the transceiver.
Connect a 50-Ohm coaxial cable with a connector type PL-259 from the transceiver output (antenna jack) to the
RF INPUT jack on the rear panel of the amplifier.
N O T E
When operating with the amplifier, do not turn on the transceiver built-in
antenna tuner (if present).
e) RF OUTPUT – should be connected to the antenna, antenna switch or tuner.
Connect a 50-Ohm coaxial cable with a connector type PL-259 from RF OUTPUT on the rear amplifier panel to
the antenna switch, tuner or antenna intended for the respective frequency band.