Connect with us

I ask a never seen electronic part.

Discussion in 'General Electronics Discussion' started by Johnny Lee, Oct 31, 2016.

Scroll to continue with content
  1. Johnny Lee

    Johnny Lee

    Oct 31, 2016
    To Whom It May Concern,

    I ask a never seen electronic part in laser pulser.

    What is a part type or name in RED Circle ?

    Thank you.

    Best Regards,

  2. hevans1944

    hevans1944 Hop - AC8NS

    Jun 21, 2012
    Could be a 4.7 ohm power resistor. Have you tried measuring its resistance with a multimeter?
    davenn likes this.
  3. Johnny Lee

    Johnny Lee

    Oct 31, 2016
    Yes, you right, But I don't know below side part of seems like capacitor..
  4. davenn

    davenn Moderator

    Sep 5, 2009
    maybe capacitors, too difficult to tell from that pic
  5. Harald Kapp

    Harald Kapp Moderator Moderator

    Nov 17, 2011
    These could also be gas discharge tubes (GDT) for overvoltage protection. As Dave wrote: difficult to tell.
    hevans1944 and shrtrnd like this.
  6. shrtrnd


    Jan 15, 2010
    Harald identified them (again).
    Jeez that guy is good.
    They're very common in the older Hewlett Packard test and measurement instruments I work on.
  7. hevans1944

    hevans1944 Hop - AC8NS

    Jun 21, 2012
    Could you tell us what kind of laser pulser you are examining? Is it a commercial laser diode pulser? Does it use a transistor operating in avalanche mode? What are you trying to do with your laser pulser? Optical radar (LIDAR) perhaps? Fiber optical communications? Please tell us what you are trying to DO?

    Attached is some background information (somewhat dated now, but still a good read) on using a transistor in avalanche mode to obtain fast rising, narrow, optical pulses from a diode laser for use in a laser-ranging application. Bottom line appears to be you have to carefully select from any given lot of transistors the ones that have the proper characteristics for avalanche-mode operation. I would hope that some progress has been made since this paper was published to allow purchase of transistors specifically made for this purpose.

    Attached Files:

    bushtech and Harald Kapp like this.
  8. Johnny Lee

    Johnny Lee

    Oct 31, 2016
    Thank for all. I tried NDYAG Laser pulser in test lab. So, I try benchmark other countries products in my school. thanks again.
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