Yaesu FT-840, TCXO-4, YF-112A boards will be made. Pro quality.

Discussion in 'Homebrew and Kit Projects' started by KD2ACO, Jun 7, 2015.

ad: L-HROutlet
ad: l-rl
ad: l-assoc
ad: L-MFJ
ad: Subscribe
  1. KD2ACO

    KD2ACO Platinum Subscriber Life Member Platinum Subscriber QRZ Page

    Hello Zeddites,
    I've acquired a nice FT-840 and have been looking without much success for the stock TCXO-4 and YF-112a boards, so I'm going to make up some with programmable oscillators from Digikey and filters from InRad. These boards will be drop in style. I need to make 3 sets of boards for the minimum order, but only need one set. If there is interest in these boards, I'll make more than the minimum depending on responses.
    all the best,
    N2EY likes this.
  2. KG7QLK

    KG7QLK Ham Member QRZ Page

    I've be interested in both. Thanks KG7QLK.
  3. KD8CDG

    KD8CDG Ham Member QRZ Page

    I would also take you up on both. Thanks, KD8CDG
  4. WU2F

    WU2F Ham Member QRZ Page

    I know this is a somewhat old thread, but I recently bought an FT-840 as a first HF radio and am also having trouble acquiring a TCXO-4 for my radio.
    While I know you have yours now and so do the other posters, could you at least post your circuit schematic so I'd be able to get my own boards made up?
    KD2ACO likes this.
  5. KJ4IYL

    KJ4IYL Ham Member QRZ Page

    I am looking for a yf-112a also. Love that radio for ssb but swl is rough. There was a website I ran across a year or so ago, where a Canadian guy was building them but I cannot find it now. Perhaps he isn't making them any longer. If anybody has any info I would be interested.

  6. KD2ACO

    KD2ACO Platinum Subscriber Life Member Platinum Subscriber QRZ Page

    What happened with this project is that after careful measurements, it turns out that the stock oscillator is fine and a slight improvement, if achievable, didn't justify the cost to make new boards and get some oscillators programmed ($$$, not a stock frequency). It also turned out that InRad makes a little adapter circuit board that fits in easily and they include that for free! Just tell them what radio you're installing the filters into when you order them.

    I gave that radio to a friend in need a couple years back and it's still working great. :)
    W2TMS likes this.
  7. W2TMS

    W2TMS Ham Member QRZ Page

    So are you saying by simply adjusting the trim screw next to the crystal is sufficient? Im having this issue and wondering how you resolved.
  8. KD2ACO

    KD2ACO Platinum Subscriber Life Member Platinum Subscriber QRZ Page

    I must have been lucky. I've got a "cell tower pull" rubidium standard for my HP freq counter for kicks and the oscillator in my 840 was very close and not drifting around at all. It was going to be ridiculously expensive to make the fixtures to program an oscillator like this one, so there were no takers at the time.


    Sorry that you're having trouble!
    W2TMS likes this.

Share This Page