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2-3. Connecting the amplifier within the shack
W A R N I N G
Before you connect the amplifier to external grounding, you should
advise with a licensed electrician and check-up whether such kind of
connection is allowed by the national and local electrical code, safety
rules, and regulations in force. Simultaneous connection to the earth
grounding and bonding may be inadmissible or may fall under special
requirements in some countries!
W A R N I N G
Never use the gas installation tubing as grounding. This can cause an
EXPLOSION!
W A R N I N G
Do not use the steam-heating or water-supply network tubing as
grounding! Thus, you may involuntarily expose to dangerous voltage
not only yourself but also other people using the same installation.
C A U T I O N
Have in mind that the grounding installation will have to withstand
emergency currents above 15A with minimal voltage drop on it thus it may
be necessary to improve its conductivity using heavier leads and lower-
resistive grounding path. The grounding lead should be at least 4mm
2
(AWG 11 or SWG 13).
For details and recommendation on the grounding and RF counterpoise system concerning the electromagnetic
compatibility see also S. 3-6(g).
a) GND stud - external grounding connection of the amplifier. After having made strictly all check-ups
described above, first connect the grounding stud of the amplifier (located on the rear panel and marked
GND – Fig. 2-1) to the grounding system of the shack.
b) KEY-IN jack - amplifier input for receive/transmit control from the transceiver.
The transceiver switches the amplifier from receive mode into transmit mode (RX/TX) via grounding of the KEY-
IN input.
Connect a shielded cable from the respective control output of your transceiver, providing “ground on transmit”
(PTT), to the KEY-IN input on the amplifier rear panel (RCA PHONO jack socket – Fig. 2-1). Use a standard
“RCA PHONO” jack plug for connection to the amplifier.
The manufacturers of transceivers give different names to this output, for example: TX-GND, SEND, T/R LINE,
RELAY, PTT, and others. At some transceivers “ground on transmit” output should be activated by a software
command, a menu or via changing a switch on the rear panel or inside the transceiver. See instructions in the
manual of your transceiver.
C A U T I O N
Before connecting the KEY-IN input verify the electrical specifications of
the transceiver control output (from its own manual) to make sure of their
compatability. The signal voltage applied by the amplifier KEY-IN jack to
the transceiver control output “ground on transmit” does not 12.6V
against ground and its closed-circuit current is below 6mA. See also S. 8-
2(a).
N O T E
Your amplifier will not work if the KEY-IN input is not connected correctly. If
you experience any difficulty consult your dealer.