PJ3500M-C & PJ5000U-K
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User Manual
Rev. 1.0 - 05/04/13
terminal in the multipole socket and check the efficiency of your own grounding
system.
Check that the multi-turn RF PWR ADJ trimmer on the RF module is turned
clockwise completely (as factory setting). As such, the action of the Automatic
Gain Control (AGC) is disabled.
5.2 Operation
After having plugged in the power supply socket at the back of the machine, power
on the amplifier via the switchboard. The ON LEDs on both modules will turn on
and the forced cooling fans will start running. The LCD shows the first introductory
screenful and then switches to a screenful that indicates the forward and reflected
power values.
Turn on the exciter (at lowest power) and wait until it locks to the work frequency.
Once locked, increase power gradually and check the amplifier’s display. Increase
the exciter’s power until the amplifier’s output attains the desired value, max. 5000
watts for
PJ5000U-K
model or max. 3500 watts for
PJ3500M-C
model (keep in
mind that due to the measurement digitalization effect it might not be possible to
obtain a reading of exactly 5 kW or 3.5 kW but a lightly higher or lower value which
is perfectly normal).
Not
e:
now the amplifier is adjusted to its rated output, but
the AGC function is
not checking the delivered power
. Any changes in the driving power or in the
environmental conditions could cause slight output power changes.
In order to operate the AGC, increase the driving power by about 10%
as compared to the value required to obtain the amplifier’s desired
output level (the amplifier’s output power will increase but this is not
a hazard for the amplifier thanks to its built-in protection system).
Now turn the multi-turn RF PWR ADJ trimmer on the RF module counterclockwise
and check on the display that the power delivered by the amplifier decreases until
the desired value is attained.
Should you need to use the amplifier at a power level lower than the rated one,
proceed as follows:
•
If back-off is temporary (for instance to run a test), reduce the output power
level of the exciter until power delivered from the amplifier reaches the desired
value.
•
If back-off is permanent (to set the station’s power at a level lower than the
maximum rated output), first disable the AGC by turning the RF PWR ADJ
trimmer clockwise all the way. Then reduce driving power until you attain an
amplifier output power value equivalent to the desired level plus approximately
10 %. Finally turn the trimmer counterclockwise until the delivered power
decreases to the required level.
Now all of the machine’s operating parameters may be checked via the software
control system.
