OM POWER OM4000HF User Manual Download Page 14

Page 

14

 of 

18

 

 

 

Band 

Tune 

Load 

1.8 

30 

50 

3.5 

65 

55 

50 

85 

10 

60 

25 

14 

70 

40 

18 

70 

45 

21 

30 

65 

24 

45 

60 

28 

15 

75 

 
 
8.   Set TUNE  knob in such a way, that the TUNE-LED lights up maximum left. 
9.   Set LOAD 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 more to the right. 
10.  Repeat tuning several times according to 8 and 9, power output should be abt. 400W 
11.    Increase  the  input  power  (to  about  50-70  W)  until  an  output  power  of  approximately 
1500W    
       will be reached. 
12.  Repeat steps 8 and 9 
13.  Set TUNE to maximum output power (RF POWER LED lights up maximum right) 
 

WARNING! 

Input power can not exceed 100W, otherwise PA will be damaged ! 

 
 
After this procedure the amplifier is tuned correctly and ready to give 1500W output power in 
all operation modes. 
 
At  optimal  tuning  and  full  output  power  a  positive  max.  80mA  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 right from the position “V”. If less output is desired you can simply decrease 
the load of the transceiver.  
 
 

CAUTION 

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! 

 

Summary of Contents for OM4000HF

Page 1: ...r s Manual External Radio Frequency Power Amplifier OM4000HF Model 4000HF Array Solutions 2611 North Beltline Rd Suite 109 Sunnyvale Texas 75182 USA Tel 214 954 7140 fax 214 954 7142 E mail info array...

Page 2: ...5 3 GENERAL DESCRIPTION 6 3 1 HF part 6 3 2 Power Supply 7 3 3 Safety Devices 8 4 INSTALLATION 8 4 1 Grounding 8 4 2 Coaxial Cable 8 4 3 Control Cable 9 4 4 Mains Supply 10 4 5 Cooling 10 5 OPERATION...

Page 3: ...Page 3 of 18 7 APPENDIX 17 7 1 Block Diagram of OM4000 HF Power Amplifier 17...

Page 4: ...Automatic switching to STBY when reflected power is 350W or higher Intermodulation distortion 32dB below nominal output Suppression of harmonics 50 dBc Tubes 2x FU728F Ceramic tetrode Cooler Centrifu...

Page 5: ...e Read next safety instructions carefully first before you will start to install and operate power amplifier NEVER VIOLATE NEXT RULES WARNING NEVER ALLOW CHILDREN to play around PA or to touch power a...

Page 6: ...The amplifier is an A category product In a household it can influence other electric appliances In such cases the user is responsible to take proper actions to mitigate this disturbance CAUTION Read...

Page 7: ...ft start is provided using relays and resistors The high anode voltage is made by combining 8 x 420 V total 3360V 2 5A Each has its own rectifier and filter In the high voltage circuit safety resistor...

Page 8: ...has to be grounded properly Connect the screw on the rear panel of the amplifier to your local grounding system with a copper cable use a cross section of 4 mm2 at least Connect your transceiver to t...

Page 9: ...tching Modern transceivers they have a time delay between PTT switching and power output CAUTION If you are using and older transceiver or transmitters without time delay we recommend to connect the P...

Page 10: ...owed Do not obstruct air intake and exhaust areas of the PA The centrifugal blowers provide the necessary cooling of the amplifier even during long contests The main blower is activated by switching t...

Page 11: ...plifier in the standby mode rather than switch it off 5 1 Operation Elements There is couple of operational elements accessible or visible on the front panel BAND Band selector switch not in the pictu...

Page 12: ...50 Ohms load resistance is connected at the antenna output CAUTION The operation of a mistuned PA will cause malfunctions the increase of grid current the GRID MAX LED will light up and problems with...

Page 13: ...ifier is ready for operation 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 multi meter 7 Transmit mode...

Page 14: ...eed 100W otherwise PA will be damaged After this procedure the amplifier is tuned correctly and ready to give 1500W output power in all operation modes At optimal tuning and full output power a positi...

Page 15: ...ter abt 2 sec the control circuits will switch the amplifier back to OPR CAUTION If the fault will repeat 3 times after each other the control circuits will turn the amplifier to STBY Bringing the amp...

Page 16: ...m tube damaging contact the manufacturer or your dealer for ordering new one You will get instructuions how to change tube and how to preset proper parameters too Be very careful you will do it only o...

Page 17: ...Page 17 of 18 7 APPENDIX 7 1 Block Diagram of OM4000 HF Power Amplifier...

Page 18: ...Page 18 of 18...

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