Welcome to the new FlexRadio Community! Please review the new Community Rules and other important new Community information on the Message Board.
If you are having a problem, please refer to the product documentation or check the Help Center for known solutions.
Need technical support from FlexRadio? It's as simple as Creating a HelpDesk ticket.

Vector Network Analyzer mode?

Ken - NM9P
Ken - NM9P Member ✭✭✭
edited June 2020 in New Ideas
Here is a "dream" idea for way down the pike.... With such a wonderful wide panadapter display, could special software be written that would allow the 6000 series to function as a VNA (Vector Network Analyzer)? It might need to be a loadable subroutine that wouldn't stay resident in the machine, but could be loaded up as part of a special "Test Equipment Mode" or something like that. (saving valuable memory and CPU cycles in normal operation.) How cool would it be to hook up an antenna (or other circuit) and have a graphic display across 14 Mhz, or two panoramas combined to 28 Mhz wide detailing the SWR and impedance figures of the antenna! Or perhaps use it as a TDA to sniff out shorts, opens, or impedance bumps in the feed line? We already will have a pretty nice spectrum analyzer and RV volt meter. Why not add to the "tool kit with a VNA/TDR, etc? I know, I could just buy a MiniVNA for $300, but I will already have a $4300 piece of equipment. If it would work, why buy another piece of equipment? I can see it now.... Is your antenna giving you problems? Switch to VNA Mode and "see" your antenna on the pan-screen. Think your coax just got "squirrel chewed" or "mole bitten?" Switch to TDA mode and "see" how far out the break is on your line. Is this even possible with the rig's circuitry? Just a thought I came up with today. Gerald promised that the future will bring us things that we have "never even dreamed of" ..... Well, I am starting to do some of that dreaming. Ken - NM9P
8 votes

Open for Comments · Last Updated


  • W5XZ - dan
    W5XZ - dan Member ✭✭
    edited June 2019
    for sure...bring it ON !! ( I have one, already, DG8SAQ VNWA2.6, and it IS marvelous...) 73
  • W8SJV
    W8SJV Member
    edited May 2014
    You bet! But if that's not possible, how about a 70Mhz spectrum analyzer with a 100 watt tracking generator ;-) Unfortunately I don't think the FCC would like that...
  • Mike W8MM
    Mike W8MM Member ✭✭
    edited July 2019
    VNA and TDR functions might be very possible from the "Transverter" port as the test output with SCU-A and/or SCU-B RF Inputs as the sensing ports. I don't know enough about VNAs to know whether one can do accurate phase information without using quadrature inputs and therefore be able to do it with a 6500. I feel confident that the general electrical functionality is there, but it might require a pretty large software engineering project to successfully implement. It might also require external directional couplers, etc. I think it would be VERY cool of the radio was its own "Field Fox" in a box.
  • W5XZ - dan
    W5XZ - dan Member ✭✭
    edited June 2019
    Alex, VE3NEA, had VNA software in his "Rocky" for softrocks. Phil, VK6APH, has VNA software for the HPSDR "Hermes"... so, it seems plausible this might happen for us too ?? 73
  • Ken - NM9P
    Ken - NM9P Member ✭✭✭
    edited June 2020
    Even though I am the original poster on this topic, I wouldn't be surprised if the guys at Flex already had this on the back burner. If not, I claim the bird-dog fee!
  • W5XZ - dan
    W5XZ - dan Member ✭✭
    edited December 2016
    no way Jose !! i asked for this last fall...' I ain't got a witness, you know I can't prove it, but that's my story, and I'm stickin to it..' ha ha ha
  • K4EAR
    K4EAR Member ✭✭
    edited April 2014
    Get an AIM 4170 and don't look back for antennas/feedlines.
  • W5XZ - dan
    W5XZ - dan Member ✭✭
    edited December 2016
    I feel the same way about my VNWA2.6. They'll have to pry it from my cold, dead hands...that is, unless or until my 6500 can do the same thing....73
  • Robert -- N5IKD
    Robert -- N5IKD Member ✭✭
    edited March 2015
    I was also thinking about the ability to have the radio act as an antenna analyzer. We could get a good profile of the antenna without swapping out the radio for the analyzer.
  • WA6FXT Mike
    WA6FXT Mike Member ✭✭
    edited September 2016
    Yes, the various VNAs available are nice and I would not throw it out, if I had one, just because my Flex6700 could now do it; however, I would much rather have the feature added to my paid for radio, rather go out and buy another box. :^)
  • WA6FXT Mike
    WA6FXT Mike Member ✭✭
    edited September 2016
    See my 'Idea' Front Panel Display...
  • Dale KB5VE
    Dale KB5VE Member ✭✭
    edited January 2017
    There is no limit!!!
  • KD0RC
    KD0RC Member, Super Elmer Moderator

    Hi Ken, I would love to see this come to fruition. The little network analyzers are getting more and more functionality. Next thing you know, they will become QRP transceivers. Time for the Flex rigs to become antenna analyzers/VNAs to keep up!



  • Stan VA7NF
    Stan VA7NF Member ✭✭✭

    No one has replied that back on introduction of the 6000 series, Steve requested users supply a list of alternate functions. I wouldn't be surprised that military customers may have received the same poll. Imagine an in-field (substitute FD / DX-expo / SOTA) a high capability diagnostic tool that, with a setting change, switches to the RX/TX function.

  • W5XZ - dan
    W5XZ - dan Member ✭✭

    Me too; a good while back this was requested, but management did not show much interest.

    I have a DG8SAQ VNWAt, and now see that stand alone units <<$100 from china are available.


    73, w5xz, dan

  • Bob G   W1GLV
    Bob G W1GLV Member ✭✭

    Let's finish the radio so it is in line with radios costing approximately the same as a Flex. This radio is starving for features commensurate with SDR transceivers. I haven't seem an upgrade for a longtime. The legacy radios will soon be ahead of Flex in features. The Flex is a fine radio but it needs further development.

  • Ken Wells
    Ken Wells Community Manager admin

    As the Original poster, I want to remind us that this post was made in August, 2013, not long after I receive my 6500 as an "early release" radio.

    The post was "...a "dream" idea for way down the pike...."

    In the early days of the release of the 6700 and 6500 we were all flooding Flex with every manner of creative and sometimes useful brainstorming ideas for performance enhancement.

    I would still love to see this function, but it is still very much "...a "dream" idea for way down the pike...."


  • W5XZ - dan
    W5XZ - dan Member ✭✭

    yes, a true 2 port VNA would sure be nice...

    e.g. i'm wondering about this old long piece of coax...a quick

    S21 scan will tell me if it's junk or not...and what the velocity

    factor REALLY is at the freq of interest? Is it an appropriate

    length delay line for a multi element phased array?

    or, i wonder what the loss and surge impedance of the blue-white

    twisted pair in a loooonnnngggg cat5 (or 6) cable REALLY is???

    or what's the actual gain of this preamp vs. freq? or the freq response

    of a homebrew LPF, HPF, or BPF filter ?

    73, w5xz, dan

Leave a Comment

Rich Text Editor. To edit a paragraph's style, hit tab to get to the paragraph menu. From there you will be able to pick one style. Nothing defaults to paragraph. An inline formatting menu will show up when you select text. Hit tab to get into that menu. Some elements, such as rich link embeds, images, loading indicators, and error messages may get inserted into the editor. You may navigate to these using the arrow keys inside of the editor and delete them with the delete or backspace key.