Through-hole JFETs going extinct

Discussion in 'Homebrew and Kit Projects' started by N1OOQ, Aug 26, 2018.

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  1. N1OOQ

    N1OOQ Ham Member QRZ Page

    Seems like in the last year or so, all of the RF JFETs we use have gone obsolete... MPF102, 2N4416, J310, etc.

    You can still get the "switching and chopper" types, good to abt 1MHz, and surface mount stuff.
     
  2. W7UUU

    W7UUU QRZ Lifetime Member #133 Volunteer Moderator Life Member Platinum Subscriber QRZ Page

    Maybe at Mouser and Digikey but it's going to be years before you cannot find an MPF102 for a low price. I just checked eBay and there's bazillions of them available for cheap. Just stock up now :)

    Seriously - just the one single ad on eBay (image below) would be about 10 times more MPF102 JFETs than I will need for the rest of my life :) I probably have that many in various blister packs in my junkbox already.

    The real truth is "THRU-HOLE PARTS IN GENERAL are going extinct" slowly but surely.

    Dave
    W7UUU

    upload_2018-8-26_8-34-58.png
     
    N2SUB likes this.
  3. K9STH

    K9STH Ham Member Volunteer Moderator QRZ Page

    The even better 2N4416 are still available all over the place. On eBay there are a fair number of such listed:

    https://www.ebay.com/sch/i.html?_nkw=2n4416&ul_noapp=true

    I still have a fair number of 2N4416 in the through-hole type, as well as a fair number of surface mount versions, in stock.

    Glen, K9STH
     
  4. N1OOQ

    N1OOQ Ham Member QRZ Page

    True dat.
    Yah, it'll be a while until they dry up completely. However, all the major distributors (i.e. Not surplus) now list them as "obsolete", and the vendor's datasheets are stamped "obsolete" as well. This was not true 1-2 yrs ago. Get 'em while you can.
     
  5. K9STH

    K9STH Ham Member Volunteer Moderator QRZ Page

  6. WA7PRC

    WA7PRC Ham Member QRZ Page

    ...even at yuuge prices. Four bits for a SOT-23 part is a lot better than $8 for a PTH part. :)
     
  7. K9STH

    K9STH Ham Member Volunteer Moderator QRZ Page

    There are sources other than Mouser who have the "through hole" mount parts for a lot less money.

    I do have a quantity of surface mount parts in stock that are the equivalent of the through hole parts. However, when building home-brew circuits, it is usually much easier to use the through hole parts. When working with circuit boards, then surface mount parts start having advantages.

    Glen, K9STH
     
    WA9UAA likes this.
  8. WA7PRC

    WA7PRC Ham Member QRZ Page

    SMT = no drilling = easier.
     
    KD5RJZ and K8AI like this.
  9. N1OOQ

    N1OOQ Ham Member QRZ Page

    Not if you're doing "ugly" construction. SMT=No ugly construction.
     
  10. WA7PRC

    WA7PRC Ham Member QRZ Page

    I did state SMT vs PTH. In my experience, the first million SMT solder connections flew by. In my engineering tech daze, I've had to use dead-bug technique to save prototype PCBAs from design gaffes. :)

    I've also used SMT w/ dead-bug technique for one-off & proof of concept circuits but, in ANY production quantity, that labor-intensive technique wouldn't fly.
     

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