Acom 2020S User Manual page 19

User's Manual | ACOM 2020S | 1.8-54 MHz Linear Power Amplifier
a) GROUND stud
First, connect the wing-nut grounding stud of the amplifier (on the rear panel, marked GROUND) to the
station's grounding system (see
Note that the grounding system may have to withstand currents over 20 A with
insignificant voltage drop on it. Therefore, it may be necessary to improve it
considerably, i.e., to become less resistive, with heavier leads and lower-resistive ground
path. The grounding leads should be at least 8 mm² (AWG 8 or SWG 10).
For details and recommendations on the grounding and RF counterpoise system concerning the
electromagnetic compatibility see also Section
.
problems
b) KEY-IN connector
This is the amplifier's input for receive/transmit control from the transceiver.
The transceiver controls the amplifier from receive mode into transmit mode (RX/TX) by grounding of the
KEY-IN input.
Run a shielded cable from the "ground on transmit" connector or terminal on your transceiver to the
amplifier rear panel KEY-IN connector (see
KEY-IN connector uses a standard RCA phono plug.
The switching voltage presented from amplifier KEY-IN connector to the transceiver
"ground on transmit" output does not exceed 12 V (positive to the ground). The closed-
circuit current is below 6 mA (see Section
Your amplifier will not work if KEY-IN input is not connected properly.
Transceiver producers give different names to this output and they are for instance
TX-GND, SEND, T/R-LINE, PTT, etc. Some transceivers require that "ground on transmit"
is implemented via a software command, or by changing the setting of a switch on the
rear panel, or interior of the transceiver. Check your transceiver's manual.
c) KEY-OUT connector
This is the amplifier's transmit-enabling control output to the transceiver.
The KEY-OUT connector provides an extra control signal from the amplifier to the transceiver. This can be
used for improving the receive/transmit (RX/TX) switching safety.
June 2022
Figure 2-3 | Amplifier rear panel - Connections
WARNING
3.6.f) Elimination of electromagnetic compatibility (EMC)
Figure 2-3 | Amplifier rear panel - Connections
8.1.j) Receive / Transmit control
, Pos. (a)).
, Pos. (b)). The
).
S e c t i o n INSTALLATION | Page 19 of 76