Acom ACOM1000 - On-Line Information and Control Functions; Auto-Protection System Overview

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You might use the off-center tuning hint also to compensate for mains voltage variations in order to
maintain tube efficiency: tune to the right when mains is higher, or tune to the left if its lower than the
nominal voltage. Please see S.2-2 (Line Voltage Selection) for more than 10% difference from the
nominal.
4-4. ON LINE Information Screens and Control Functions.
a) Besides the Warming Up and TRI (described above in S.4-1 through S.4-3), you have 12 more
Information screens available. They are as follows: Forward Power, Reflected Power, Output Power
(difference between forward and reflected), Antenna VSWR, Drive RF Power, RF Power Gain, Plate
Current, High Voltage, Plate RF Peak, Screen Current, DC Power Input (product of plate current and
high voltage), and Exhaust Air Temperature (Celsius and Fahrenheit scales). You can use them to monitor
the technical state of the amplifier and the associated parameters in digital form.
Selection is made by the PREV and NEXT buttons. You may change them in a closed loop, while the
amplifier is used and controlled in operate and standby modes, changes transmit and receive, without
any influence by the measuring process.
b) You can control LCD adjustment and Auto-Operate feature selection also while ON LINE. The
method is the same as it is described for OFF LINE, so see S.5-1 and S.5-2 for details.
4-5. Auto-Protection System
When any abnormal condition is detected, the amplifier will evaluate the risk and may use three different
degrees of protection, depending on the nature of the problem. Each event is accompanied by a text
telling you the reason. The backlight of the LCD is flashed meanwhile in order to attract the operators
attention.
a) The first degree of protection is issuing a warning message only, without any influence on the
transmitting process. This might be for instance Reduce Drive, Plate Current, etc. You could continue
to transmit under such conditions but you are close to a trip threshold.
b) The second degree of protection is a trip in standby mode (Soft Fault). Youll get an appropriate
message, for instance ** GRID CURRENT **. All Soft-Fault messages are marked with two asterisks on
both screen edges. The message remains on the display until you press any button (or auto-operate
function returns to operate mode automatically). The Soft Faults are of such kind where you can correct
exploitation conditions operatively (using less drive, improving VSWR, etc).
c) The third degree of protection is a trip in off mode (Auto-Protection).
Youll get the corresponding signature (see S.6-5 - Troubleshooting). If you cannot guess what is the
reason, you may try to turn the amplifier on again in order to check whether its not an accidental
condition. If the problem persists, youll need to contact your dealer - see S.1-2.
N O T E
The 6dB input attenuator is automatically inserted about 1 second after a bad tuning
is detected at drive levels above 20W. It is switched off at every PTT release (unless
inserted manually).