OM POWER OM4000A, Инструкция по эксплуатации

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The amplifier is prepared for operation with the following automatic steps:
 Toroidal transformers are switched on step by step.

The cooling blower for the final tube is switched on.

The multi-meter bar graph measures the high voltage; the normal value is 3.3 KV

The WAIT LED lights up.
CAUTION
After switching on, please confirm that the blower is operating properly. Air must be flowing
from the ventilating aperture above the tube. If there is any concern, or no air flow, press
the “OFF” button immediately!
Heating of the tube takes about 180 seconds . After this time the WAIT LED goes out and the
amplifier is ready for operation.
Enter TUNE mode. Depending on the input power level and antenna parameters, two situations
can occur. First , when your antenna parameters are close to real 50 Ohms, and input power not
exceeds allowed maximum, PA stay in OPR mode and you will see the output power. You have
to do just little adjustment (steps 8, 9, 12, 13) to get maximum output power.
Second , if your
antenna parameters are not very good and input power is higher than 15watts, safety devices
will switch PA automatically to STBY. In such a case start with step 4, go thru all next steps.
4. Reduce the power output of your transceiver to the minimum!
5. Switch OPR/STBY to OPR position (OPR LED lights up).
6. Choose the TUNE position of multimeter.
7. Transmit and increase driver power to cca 10W.
CAUTION
If the input power is higher than 15W and the power amplifier is not correctly tuned, the
safety devices will switch to STBY. The amplifier will automatically reset and switch back to
OPR mode after approximately 2 seconds. Meanwhile, reduce the input power.
8. Set TUNE knob in such a way, that the TUNE-LED lights up maximum left (multimeter in
TUNE position).
9. Set LOAD knob in such a way, that the TUNE LED on the TUNE scale lights up under the
“
V ” sign. If it is possible to obtain the LOAD in 2 positions, set the position that is further
to the right.
10. Repeat tuning several times according to 8 and 9, output power should be abt. 600W.
11. Increase the input power (to about 50-70W) until an output power of approximately 4000W
will be reached.
12. Repeat steps 8 and 9.
13. Set TUNE knob to maximum output power (RF POWER LED lights up max. right).