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6600M - SSB vs. CW amp drive level

Andy - KU7T
Andy - KU7T Member ✭✭
edited January 2020 in FLEX-6000 Signature Series

Sorry, if this is a rookie question. I am a SSB rookie :-)

I know about PEP vs AVG power and the 2.5dB gain of CESSB with the PROC ON. I have an Elecraft W2 watt meter, and find its PEP mode does not really work well. 

I do not know exactly how to set my output power to drive my solid state amp in SSB (or to set it any differently from CW). In high duty cycle modes like CW, all is easy. All I do is put a carrier out, adjust to what I want to go out (i.e. for 1.5kW I set SmartSDR to 29W out). My question is how to do this in SSB. 

Do you simply keep the SmartSDR drive level at the same point where you would set it for CW or do you increase it a bit? I am asking because when I do that my watt meter shows 100-400 watts in SSB, and as I do not trust the PEP feature on it, I am looking for an easy fire-and-forget solution. Also, I do try to keep my MIC gain high so the peaks are at the end of the yellow just below red.

Thanks and 73


  • Bill English
    Bill English Member
    edited January 2020
    If you need 30 watts to get 1500 out, you adjust it in CW, and simply switch the mode to SSB and talk. I do not have a different setting for SSB and CW. I control my amp via DDUtil and it allows me to set an AMP1 and AMP2 drive levels for each band via the PC to the amp. I have amp one set for full output and I have amp two at about 1/2 power to use in RTTY. 

  • Mark WS7M
    Mark WS7M Member ✭✭
    edited March 2019
    As Bill says that is pretty much it, EXCEPT I would add that your mic gain is critical.  You want to see your peaks JUST touching into the red.  Any further and you can get some bad artifacts on your signal.
  • K0FLY
    K0FLY Member ✭✭✭
    edited March 2019
    As you talk what is the compression meter doing.  You should be seeing some action on this gauge.  When i first got the flex , other stations had a hard time copying me, in fact My S-Line did a much better job.  I had the flex equalizer settings  around zero dB, I found that if I pushed the EQ settings up about 5 dB I started seeing  compressor action and received  better signal reports.. My LP-100 was reading higher also.

    Gayle K0FLY

  • Mark WS7M
    Mark WS7M Member ✭✭
    edited March 2019
    I am a firm believer that you can get good audio without much if any compression.  I would personally strive to get your audio spectrum, using Ken's video method to have good energy shown across the audio range of your voice.

    As Ken points out in the video you can have different profiles for different things.  So you might have a good all around ragchew profile with little compression but good energy across your voice spectrum.

    then you might want a DX profile using the same spectrum but enhance the key frequencies used in word recognition and add in compression.

    I think compression is a good tool, just try to get the most out of your voice using the equalizer first.
  • John KB4DU
    John KB4DU Member ✭✭✭✭
    edited March 2019
    In the broadcasting/ audio world, the general rule is to cut before adding. The eq can't boost what isn't there. For the Flex, I suggest some cut below 250, not much voice intelligibility that low. If the High cut on the TX filter is set to 2900 or so, the upper freqs on the EQ will get cut anyway. Proc to whatever you like, DX works best for me, then MIC gain up until some compression shows some, keeping the MIC level below zero, where clipping/distortion starts. YMMV.
  • Tom OBoyle
    Tom OBoyle Member ✭✭
    edited December 2019
    Hi Andy -

    I too see this and am not sure on the correct answer. 

    I have a PGXL Amp and have been primarily CW operator before.  I can set the radio to 30 watts CW for 1500 watts out.  If I leave at 30 watts and switch to SSB, I see 200 - 400 watts PEP out on my Diawa meter.  If I move the power to 50 watts drive, I can see 600 watts or so.  This is pretty similar to value on the Amp's meter as well.  

    If I adjust the audio and overdrive it, I might be able to get 900 to 1000 watts out.  If I adjust the audio so that I am not over driving the mic and set the RF drive to 75 watts or so, I can get 1200 watts out BUT I am afraid I am putting out a bad/dirty RF signal then.

    What is the right answer here?  How do others get 1200 - 1500 watts PEP with 30 - 50 watts of drive and not over-driving the mic?

    73 de Tom, N9GUN

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