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MB1 User Manual
© 2016 Expert Electronics
CONNECTIONS
Also you may want to send audio signals to the transceiver and/or receive them from the
transceiver.
To do that you may use MB1's audio cards (on the rear panel) or the audio cards of the other
PC.
2.5.3
External Linear Amplifier
You can connect external Power Amplifiers (PA's) to the transceiver.
It may be required to connect more than one Amplifier depending on the type of the external PA
wanted.
Connect a 50 Ohm HF cable to one of the transceiver's antenna connectors HF1 ... HF4 (SO
239) or VHF1 ... VHF2 (N-type), if it is VHF band PA. The other end of the cable connects to the
input of the PA.
If the PA can be controlled via the CAT system, for switching bands and / or tuning of the HF
circuits, you can use the "null modem" COM-port cable to control the amplifier.
To switch the PA to the transmission mode,normally you use a connection to the PA's control
line and the PA's case. The MB1 transceiver provides four separate PA PTT sockets for
connecting the control lines and the case, for four external PA's. Use one of the lines to control
a PA's transmission mode with RCA-type phono plugs. You can set the switching delay of an
external PA from RX to TX and back from TX to RX, in the transceiver's settings, if required
(more details in
).
If an external PA supports communication with the transceiver's ALC system , you can connect
it via cable with RCA-type phono plugs. The voltage adjustment range for ALC -3...0 V (see
warning below).
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