[Amps] 811 Update

TROY D SINGLETON-N5ARK N5ARK at COMCAST.NET
Fri Nov 2 20:20:28 EST 2007


It is working! Actually doing a little better than expected! It loafing about 675 to 700 Watts with the new set of Penta Tubes. I was about to take some pics to describe things for me and I got a can of air and gave it a good blowing out and then I decided to try it one more time and everything is working great! But I am sure I will still do more QRP but at least I have a amp if I need one. And I guess it proves another good point...Just a little blowing will bring some things back to life!....

Thanks everyone for helping me,

Troy N5ARK
  ----- Original Message ----- 
  From: Jim Kennedy 
  To: N5ARK at COMCAST.NET 
  Sent: Friday, November 02, 2007 7:41 PM
  Subject: Amplifier


  Hi Troy, My name is Jim and my call is W6OUU. I have been reading with interest you trial and tribulations that you have been having with your amp. I see that you discovered the tube problem as far as orientation in the sockets is concerned and not have them all running. I have noticed that your remarks say that nothing is happening when you turn the plate or load controls is that correct ??  This is how I would approach the amplifier if it had just walked into my shack.



    1.. Check and make sure that everything mechanically is where it ought to be and nothing is loose or rattling around in the cabinet. 
    2.. Check to make sure that the fuses or circuit breakers are of the proper value and installed. 
    3.. Connect your transceiver coax to the amp and the keying line from the transceiver to the amp. 
    4.. Connect your antenna or dummy load with of course a wattmeter in line to the amp so to measure power output. 
    5.. With the amp OFF transmit with the transceiver and make sure that the by-pass circuit in the amp is functioning. I do this in the cw/tune mode. You should have on the wattmeter whatever the transceiver is putting out at this point. 
    6.. Now to test the amp. Set the band switch to the band and the Tune control to the band if it's marked. The Load control should be set at minimum. 
    7.. Set the power switch to on. Observe that the tube filaments are lit and there's no abnormal sounds present. 
    8.. On the amp- if it has a meter switch-turn it to volts and see if you have a reading. That would be the plate voltage. If you don't then something is wrong. If you have plate voltage continue to the next step. 
    9.. If the amp has a cw/tune/ssb position, position it in the cw/tune. 
    10.. Switch the meter to plate current 
    11.. Set your transceiver to SSB 
    12.. Key your radio-----you should probably hear the amplifier key and there should be an indication of resting plate current on the meter. If there isn't then I would think there is a problem. If there is an indication of resting plate current when keyed then proceed to the next step.( Not knowing the amp I would think a resting plate current of 100-200 ma would be in the ball park.) 
    13.. Switch your transceiver back to cw/tune and decrease the output to its lowest level.. 
    14.. Key your transceiver and slowly increase the output. The plate current on the amp should increase above the resting plate current when it begins to take the drive, when it does that tune the plate tune for max output on the wattmeter. If all is well you should see a dip in plate current as you get max output. Increase the load control a slight amount and then back to the plate tune, always peaking the wattmeter for best output. Continue doing this until you have the desired results for your amplifiers ratings. 


  I hope this is of help to you. If you have any questions feel free to contact me.



  Jim W6OUU








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