HV-UNIT 

1. Control  of  the HV Unit:

Switch on the PA, push the red HV knob on the front panel. The LED bargraph will sign the actual anode voltage.
On case if we have high voltage voltmeter we can check the anode voltage on pin 5th of  the JP7 connector.
We can calibrate the HV meter with the P1 poti on the HV unit.

2. MODIFICATION on the HV unit:

   - On the old HV unit versions we used 10 Ohm/5W resistor on place R24. Change please this resistor to 220 Ohm/3W resistor
    to better Ip measurment. After replecament have to recalibrate  the Ip meter: Put the PA to TX without drive. (PTT input Jack is on    
   the  GND) Check the voltage on the R4 10 Ohm resistor on the UCU-01 control unit. Set 1.0V  on R4 with P6 poti on the UCU-01.
    Calibrate the Ip meter with P5 poti on the display unit. (This modification is recommended on the every old HV unit!)

    - We moved the HV fuse to rear panel on the new models. (Much easy to change the fuse on case any HV problem on the HV PCB)
      Please remove the PCB fuse holder from the panel. Remove the wires from original F3 fuse on the rear panel and please short
      the old wires.
      Please solder two  new isolated wires to the F3 fuse holder and connect the ends to the  ends of the panel fuse of the HV unit.
      ( we use 2 pol. PCB connector on new versions.) Change the F3 fuse to 1.25A type.
    - Cut the panel line btn  -HV point of the rectifer diodes and the R24/C9 capacitor. Connect R24/C9 with a short wire to pin 1 of the
      JP7 connector.(after this modification the HV meter will not sign if the F3 fuse is broken.)





















3.    VOLTAGES on  JP7 connector.

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