User's Manual | ACOM 2020S | 1.8-54 MHz Linear Power Amplifier
Page 40 of 76 | S e c t i o n OPERATION
June 2022
4.3.
Automatic Protection System
The ACOM 2020S control unit (see Section
7.4 Using the Fault Codes (signatures) for Diagnostics
) keeps track of
most amplifier analogue and logic signals in all modes.
Those are the receive/transmit control signal, the output relay contact state and switching times, the RF
drive frequency and drive power (the input power), the final transistors DC current and DC voltage on the
drains as well as, the gates bias voltage and the heat sink temperature, the main power-supply components
temperature, the RF output forward and reflected power, and others. Some derivative parameters, as the
power gain, the antenna SWR, and others, are watched too.
In the event a parameter limit is violated, the amplifier will assess the risk and will trigger one of the three
levels of protection, as described in items (a) to (c) below. Every event is accompanied by a warning text on
the screen (see
Figure 4-1 | Appearance of an alarm message
). A sound alarm will be also produced, if set on
in the USER PREFERENCES menu (see Section
Figure 4-1 | Appearance of an alarm message
Figure 4-1 | Appearance of an alarm message
a)
First protection level -
WARNING
The first (most forgiving) protection level is a WARNING. When a value watched by the control unit
approaches the protection threshold, the transmission is not interrupted, but a message appears - for
example "Drive Power too High", "Drain Current too High", "Reflected Power 120 W" or another (see
4-1 | Appearance of an alarm message
).
You can continue to transmit in these conditions, but you may take some measures, for example, to reduce
a bit the drive power from the transceiver. The warnings remain on the screen for at least three seconds so
that they can be read through and will disappear after the reason has dropped off.