OM POWER OM2200A, Manual

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10. Repeat tuning several times according to 8 and 9, output power should be abt. 500W.
11. Increase the input power (to about 50W) until an output power of approx. 2200 W will
be reached.
12. Repeat steps 8 and 9.
13. Set TUNE knob to maximum output power (RF POWER LED lights up max. right).
After this procedure the amplifier is tuned correctly and ready to give 2200W output power
in all operation modes.
At optimal tuning and full output power a positive max. 50mA current goes through the
second grid. On 24 and 28 MHz bands optimal tuning can be achieved when one or two LEDs
are lit up to the left from the position “V”. If less output is desired you can simply decrease
the load of the transceiver.
Should the amplifier demonstrate any malfunctions during tuning or should it not
behave in accordance witch the description, interrupt the tuning procedure immediately
and check the amplifier! Be sure to have not done any mistakes in choosing bands or
TUNE/LOAD values! Be sure that VSWR is not higher than 2:1 and input power is LOW!
After excluding possible human mistakes you will be able to work for long time with this
amplifier!
5.3.3. Tuning Adjustment
Entering the
TUNE mode is done by pressing the TUNE button. The OM2200A then switches
the transceiver to RTTY and sets the frequency to corresponding segment. By changing the
values of TUNE and LOAD capacitors we tune the PA as per manual tuning instructions (see
5.3.2.). The optimally tuned amplifier will deliver full output without approaching the
maximum Screen Current of 50mA!
After tuning the amplifier save the settings by pressing SET and PA will automatically tune
frequency of your transceiver to next band segment.
Follow the same procedure for all bands
and segments if needed.