Quick and dirty PSK leads for FT-857

I was itching to get on the air with my new FT-857 so I made up a quick and dirty set of simple interface leads.

The FT-857 has a data port on the back and a digital mode that is selectable from the menu system. It also has a data port VOX function so any audio being presented on the data port will activate the TX.

You need a 6 pin mini din plug and 3 x 3.5mm mono jacks.

Make up 2 leads. 1 with a 3.5mm mono jack on each end and one with a 3.5mm on one end and the 6 pin mini din plug on the other end.

The 6 pin mini din is wired ground to pin 2 and tip to pin 1. This is a view with the plug face down on the bench, ready to solder.

Put the 6 pin mini din in the data port on the FT-857 and the 3.5mm on the other end into the line out jack on the PC.

The 3.5mm – 3.5mm lead goes into the speaker out of the FT-857 and the other end goes into the mic or line in on the PC.

Don’t forget to set your input/output levels correctly (no ALC should be active on the transmitted audio) and turn on the VOX function in the menu (number 040) on the FT-857.


Marcelo has pointed me to a much better diagram of the FT857 data jack. Note that this is an image showing the port on the back of the radio. http://goo.gl/xmTgK

12 Replies to “Quick and dirty PSK leads for FT-857”

  1. Hi, Matt,
    Thank you very much for this idea!
    I was wondering if there is any particular reason why you are not using the same DATA plug for both, audio input and audio output.
    In the 857’s Operating Manual, pg. 18, they suggest to use Pin 5 (data out 1200 bps) if you want to connect a tape recorder. Do you think that that audio output would not work for our purpose?

    Also, it seems that there is an error in the Pin #s.
    In my 857D’s User Manual, the #5 is at right and #6 at left, but, in your image, the #5 is at left. However, Pins #1 and #2 are OK.
    Thanks for your time, 73,
    Marcelo W8/XQ6BQ

  2. Hi Marcelo, I did try using the data jack for audio out but I could not get enough volume out of it and into my cheap pc sound card. I would love to know how you get on if you do use the data out for audio.



  3. Hi Matt,
    I haven’t made the cable yet, but I found a diagram with the connections for using the DATA (mini-din or PS2) connector for both, audio in and out.
    They are using other connections and components for PTT also, but I think with VOX there is no need for that.

    I still am in doubt because of the pin #’s.
    Your post says: Pin1->ground and Pin2->Tip (from PC audio out);
    but the diagram I found, as well as the FT857’s user manual, say the opposite: Pin2 to ground and Pin1=Data In (to tip – from PC audio out).
    Do you think that perhaps there is a typo or some kind of error in your post?

    (I really want to try this cable but I don’t want to make any serious mistake).

    Thanks! 73,

  4. Hi Marcelo,

    I think there is some confusion here.

    The diagram you linked to shows the female data port on the back of the FT 857.

    My simple diagram above shows the male plug as looking down from above, ready to solder. Yes, my pin numbers do not match up with the diagram but the end result is the same.

    Hope that helps.


  5. I have updated the image and text to avoid confusion!

    Thanks 🙂

  6. Thank you very much for the clarifications, Matt! Thanks to your article I got interested in making this cable by my own. Now, I’ll just do it!

  7. if you take a look at the FT857 service manual , downloadable from yaesu , it shows the pin numbering as they regard it . which is different , from a/our “normal” practical point of view ….
    This has caused confusion in mamy webpages ..
    I wish to do data tx/rx with my FT857 , and I’m ok with the audio routing , but I am totally confused where the tx port pin is wired to , can anyone help please …. ?
    27th June 2013

  8. Hi Gordon,

    As far as I can see, the image of the plug in this post (remember that it is a view looking down onto the solder buckets) matches the pin numbering for the FT-857 as shown on page 7 of the service manual.

    I guess you are trying to switch the radio into TX mode using the data port? If you are then according to the owners manual and based on the service manual diagram and my plug image above, pin 3 should be the TX pin. If shorted to ground then it should place the radio into TX mode.

    How are you trying to switch the radio to TX mode? Are you using a serial port on a PC or some other kind of control box?

    The cheap/quick/easy/dirty way to get the FT-857 to TX data is to use the VOX function (Menu No. 40) on the data port so that when audio is sent from the PC, the FT-857 automatically transmits. Make sure you turn off your PC’s sound notifications so that you don’t send out the “new email” alert sound over the airwaves!

  9. Hi Matt … I’m an old git ham … and I don’t understand any of what I’m doing … I have the rig , and wish to rx/tx Data , using the Ros program … I may have jumped the gun a bit , but I found that I could download the 957 service manual , and I felt that the pin numbers were different …. these drawings are confusing , as they do not indicate front or rear ……. it’s caused me problems on many occasions !

    I have got rx going , it seems , and it appears that the tx is operating , as the tx box changes colour when I press the Call box …. I don’t have the audio from the laptop audio connected yet , just making up at lead at this time … also , as i’m in digs , don’t have an outside aerial , just a small tuned loop , but a lot of broadband qrm here …
    its a challenge …. I can say no more , and I will do it ….
    have decided to go to the qrp rally , at south Manchester this weekend , there may be some aerials and cable there , so I can get a bit of wire up at the back of the house …
    Tnx Matt , any help is appreciated , I am in a strange world , switches and manual potentiometers are my thing !!!
    For any more advice gordonj.reason@virgin.net
    , Shipley , West Yorks .

  10. Hi, I know this is an old thread, but I’m wondering. Would this method work with using WSJT-X for FT8 ?

    I do not have to buy a “Signalink” or “U5 Link” or some other device if I do not have to.

    If it is feasible, what settings on the FT-857D would be required.

    (Also, is the current picture of the connection still the “Solder Bucket” view?)

  11. It should work fine for the audio side of things. Obviously, you won’t have rig control via CAT so you’ll need some way of activating the PTT (via VOX or external CAT control).

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