Connect with us

What the heck is this ceramic disc with fins?

Discussion in 'Datasheets, Manuals and Component Identification' started by gage, May 8, 2013.

Scroll to continue with content
  1. gage


    May 8, 2013
    I've tried the google. i've tried numbers and combinations of numbers. i don't see anything written on the other side of them. they're roughly between the size of a dime and a quarter.

    I have a handful of these things and i have absolutely no idea what they are. can anyone tell me if it's a capacitor, resistor, plutonium container, whale caltrop, or suchlike?

    thanks a bunch!

    Attached Files:

  2. CocaCola


    Apr 7, 2012
    Last edited: May 8, 2013
  3. gage


    May 8, 2013
    Coke is it, as they say! Thanks so much, now i can google the heck out of them.

    (on a related note, it appears that the whales don't have anything to worry about...)

    Really appreciate your help. I guess the new rule is, if it has a multiple of three contacts, maybe it's a transistor.

    thanks again,

  4. davenn

    davenn Moderator

    Sep 5, 2009
    just for your info
    commonly the connections are .....


    The 4 emitter pins are connected internally as shown by the black lines

    All the emitter pins go to the groundplane of the circuit board
    The larger of the 2 centre pins is usually the Collector, larger because its carrying more RF current


    Attached Files:

  5. duke37


    Jan 9, 2011
    Some RF transistors use beryllia as an insulator. Do not damage it, how would you dispose of it?
  6. shrtrnd


    Jan 15, 2010
    I don't know if this device has beryllium in it, but for trivia:
    The dust from beryllium is supposed to be toxic when inhaled.
    We use a lot of devices with beryllium in them, and yeah, we have to pay a hazardous
    waste disposal place to get rid of them when they go bad.
    But just using devices with them is supposedly alright. We're just prohibited from
    sanding, lapping, or allowing any of it to turn to dust which can be inhaled.
  7. gage


    May 8, 2013
    Thanks, all (and especially to davenn for the general case). Seems odd to have four emitters, but that's probably because i have no idea what the heck i'm talking about.

    Does look like i have some playtime for the weekend though. Still have more googling to do to find a datasheet, then it's time to break out the multimeter, arduino, etc, and go to town.

    Also, thanks, duke, for the Beryllium warning. Since i have about 20 of these things, it's good to know that crushing and snorting them is a bad idea :) (Seriously, though, thanks - I'd rather not expose myself, the kids, etc, to Be).
  8. (*steve*)

    (*steve*) ¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd Moderator

    Jan 21, 2010
    Just 1 emitter, but 4 connections to it.

    Not a designer of RF stuff, but it speaks to me of a desire to have the lowest impedance connection to the ground plane as possible. And I'm thinking Class C, but that's just a series of educated guesses.
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day