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KPA-500 on QSK

I got a KPA-500 and KAT-500 combo installed yesterday with my 6300, Very nice, using DDUtil, the only way to fly. Makes it all very safe and simple. Love the drive level by band. Works perfect.

I was playing with the QSK and I noticed there are a couple of places where the TX delay can be adjusted. In CWX where you have the QSK button there is a window with a delay set to 5. I left it alone and did not mess with the other TX delay in the TX setup.

Should I be OK with 5? I am assuming that is 5ms? Seems like I read somewhere that the time on the pin diodes in the 500 was 4ms, but I may be wrong. I was hoping some KPA-500 users could verify this for me.

I could hear fairly OK between characters with the QSK on, and my sent CW seemed OK, I got no complaints from the other end.

Just wanted to be sure. One thing is certain, it is a slick combo and it works so well with the Flex and DDUtil. I am running 22-25 watts for 500w on 80m on up to 35 on 6m for 500w. 6 is the only band where it comes close to the 40 watts drive the manual talks about. Most all other bands are in the mid 20 w range. This is a relatively new amp, it was sold in mid March and used very little until I purchased it.  


  • WK2Y
    WK2Y Member ✭✭
    edited June 2020
    I'm curious, what advantage does using DDUtil provide?  I haven't used or even looked into the program.
    Thanks & 73
  • Mike-VA3MW
    Mike-VA3MW Administrator, FlexRadio Employee, Community Manager, Super Elmer, Moderator admin
    edited April 2019
    You can also drive the KPA500 and KAT500 band data right out of the radio and no need for DDUTIL.  That is what the USB/RS232 devices do.  



  • Wayne
    Wayne Member ✭✭
    edited June 2018
    With the KPA500 you don't even need band data it has built in auto sensing for the band and switches almost instantly and flawlessly.
  • Bill English
    Bill English Member
    edited January 2020

    I like the fact that the DDUtil moves the rig to the band. I know it has freq sensing but I just like hearing it click when I change bands, I guess I'm old school.

    As far as what it does, it does everything just about. You can control the amp 100% from the PC screen. The auto-drive feature alone is reason enough to use DDUtil. Mine is set to 500w out on all bands except 30m. Of course the drive is not exactly the same on every band. DDUtil sets it to the proper drive level on a band by band basis when the amp is out of standby and goes back to 100w (or whatever you set it to) when in standby mode. It has an SWR alarm that will shut down amp and radio if it's exceeded, it has a power alarm you can set that will do the same if a power level is exceeded. It shows you the temp of radio finals and voltage, temp of amp finals, voltage, current, output power and swr. All the details of the KAT-500, you can do everything you can do from the front panel. It may not seem like a big deal to some, but in a contest having this convenience is incredible.  It even shows the current space weather. I know I am forgetting a lot of other stuff.

    You can also interface most all major watt meters. You can control everything on the Flex as well. And believe it or not this is only a small part of what it will do, it will do a lot more. I may understand 1/3 of it, if that. You can control your SteppIR from it, as well as your rotor.

    Plus it's free. Now I see why most Flexers swear by this program. It is truly amazing. I would not want to run a solid state amp without it. I am spoiled.


    Bill K4FX

  • WK2Y
    WK2Y Member ✭✭
    edited January 2020
    I guess I will be looking into that one.  I'm already hooked on Slice Master and FRStack.  
    Thanks and 73.
  • Larry Benoit
    Larry Benoit Member ✭✭
    edited November 2018
    Some operators may want fuller control of the KPA500, including power on/off, OPER/STBY with PA temp, fan speed, current and voltage monitoring. DDUtil handles it all nicely. The Flex USB/serial cables provide only band data, which is actually redundant, given auto band-switching. Alternatively, Elecraft provides remote control software for the KPA500. 

    Larry KB1VFU

  • Bill English
    Bill English Member
    edited April 2018
    Bob, i didn’t have FRStack. I installed it after you mentioned it and I really like it! I kinda missed the band stack register and now I have an improved one. One slick program. I’ve only gotten back on Flex radios in February, still have a lot to learn. Thanks Bob Bill K4FX
  • Patrick
    Patrick Member ✭✭✭
    edited April 2018
    Has an extra measure of remote controle over just sending band data.
  • WK2Y
    WK2Y Member ✭✭
    edited April 2018
    Glad you like it.  Took me a bit to figure out how to best take advantage of it but now I load it up every time I start the rig.

    73, Bob

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