Convert high voltage keying to positive keying

Discussion in 'Straight Keys - CW Enthusiasts' started by VK3MTW, Aug 27, 2021.

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  1. VK3MTW

    VK3MTW Ham Member QRZ Page

    Hello hams.
    I have done some searching and found I need to build the relay so I can use positive keyers into the radio.
    I have found a few posts about this but the answers are very blunt to explaining how to build one of these.

    Can anyone help me with some photos or drawings ect, on this "simple build"

    Thanks.
     
  2. KG7WGX

    KG7WGX XML Subscriber QRZ Page

    You could get one of these, assembled -

    http://www.hamgadgets.com/UKA-2

    Relatively inexpensive at $35.
     
  3. K5UJ

    K5UJ Ham Member QRZ Page

    My solution was to get a Hallicrafters TO Keyer and Vibrokey paddle. But I'm a bug guy so this solution worked for me.
     
  4. K1LKP

    K1LKP Platinum Subscriber Platinum Subscriber QRZ Page

     
  5. K1LKP

    K1LKP Platinum Subscriber Platinum Subscriber QRZ Page

    HEY,,,,, YOU OLE BUZZARD.......

    CONGRATS ON BEING THE PROUD OWNER
    OF A HA-TO KEYER.......BRAVO......

    ======================= w9to HA_LOGO.jpg

    W9TO_KEYER_JIM.jpg

    w9to Jim_ricks_march_2017.jpg

    https://www.qrz.com/db/k1lkp

    73 ES HAVE A FUN FILLED WEEKEND

    LIKE I LUV CW & CFO.jpg
     
  6. K1LKP

    K1LKP Platinum Subscriber Platinum Subscriber QRZ Page

    HI MATT,

    YEARS AGO I BUILT A VERY SIMPLE SIMPLE CKT JUST USING A RADIO SHACK REED RELAY


    https://www.radioshack.com/products/spst1a-12v-rd-rly

    RADIO SHACK IS NO LONG IN BIZ.

    IT LOOKS LIKE IT IS AVAIL ON AMAZON


    https://www.amazon.com/0-5-Amp-SPST-Reed-Relay-12VDC/dp/B007Z7NLHA

    I WANTED TO SHOW U YOUR OPTIONS.

    THIS TYPE OF REED RELAY WUD KEY THE DRAKE TR-4 UP TO 70 WPM.


    HAVE FUN AND BE CREATIVE.

    JUST USE LOW VOLTAGE TO KEY THE REED RELAY AND THE
    CONTACTS IN THE REED WILL DO THE REST.

    73 - K1LKP
     
    Last edited: Aug 27, 2021
    AD5HR likes this.
  7. VK3MTW

    VK3MTW Ham Member QRZ Page

    Thanks I have looked into these Reed relays.

    From what I know I use the positive from my keyer to the two coil pins of the relay and the other 2 will close the radios high voltage cw line. Is this correct?

    Cheers
     
  8. K1LKP

    K1LKP Platinum Subscriber Platinum Subscriber QRZ Page

    MATT,

    ARE U JUST TRYING TO KEY AN OLE BOAT ANCHOR XMITER.........

    IF NOT ..... NEED A LITTLE MORE INFO ABT THE CKTS YOU ARE TRYING TO
    ENABLE ??

    THANK YOU
     
  9. VK3MTW

    VK3MTW Ham Member QRZ Page

    Yes exactly what I'm after
    Using a mfj keyer into a boat anchor

    I'm thinking I can put a Reed relay in to a patch lead from mfj to the radio with the mfj side on the switch coil and then the radio end on the other two. Might be able to heat shrink it nicely on a patch lead. Will just have to mark witch side is witch when I'm done.

    Will the mfj have enough power to close the relay? I might test how much power the mfj keys tonight.
     
  10. KG7WGX

    KG7WGX XML Subscriber QRZ Page

    I believe most keyers act like a switch, with the wetting voltage applied by the rig. As the relay has no power, you will have to provide for this.

    Select a power supply within the operating range of the MFJ and suitable for the operating voltage of the relay.

    The contact rating of the relay should be high enough to handle the boat anchor's voltage at the key input.

    If the power supply for the MFJ keyer has the capacity, you could use it to power the relay as well as the keyer.
     
    Last edited: Aug 28, 2021

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