need replacement transistor

Collapse
X
Collapse
 
  • Page of 2
  • Time
  • Show
Clear All
new posts
Previous 1 2 template Next
  • xelectech
    retired tech
    • Nov 2014
    • 238
    • USA
    #21
    Re: need replacement transistor

    Hey, thanks for the link, nice site!

    So, is that a no?

    The data sheets I found were somewhat different on a few of the values, but the breakdown voltages are listed as a negative V. I didn't figure that there would be any Vs more negative than -5 so I disregarded the breakdown voltages.

    Also the transition freq. is the same for both of them on the alldatasheets site, though the collector capacitance is listed as 20pf for the 2sb647.

    Wish I still could remember all that transistor stuff from tech school...
    Anyway, guess I'll keep looking, and maybe order one when I figure out my next caps order.
    Last edited by xelectech; 02-13-2016, 09:15 AM.

      Comment

      Previous 1 2 template Next

      Related Topics

      Collapse
      • Haaheim
        Bias matching replacement transistor - Parasound 2250
        by Haaheim
        Hi guys!

        I am currently working on a Parasound 2250 (class AB), which had one defective channel. Components in the signal paths have been replaced, including an output transistor (2SC3519).



        According to the manufacturer, bias is adjusted by measuring 1-3mV across the output resistors. The original ones are completely fine around 1.5mV, but the replacement is not. Initially, I got a couple from eBay, assumed they were fake (they were) and was able to source a replacement locally. This exhibits similar behaviour, being around 0.6-0.8mV on its emitter resistor....
        05-13-2022, 12:45 PM
      • reformatt
        Macbook Air M2 A2681 Kernel panics after screen replacement
        by reformatt
        Just had a customer bring in a M2 MBA A2681 that had had a screen replacement in April at another repairer. Since then, she has been getting intermittent kernel panics. It's an aftermarket screen, and of course it fails in diagnostics as the calibration hasn't been done. The error in the panic log is "No device added after powering on the rails".

        It seems the original repairer has swapped the board and the screen to other MAC's, and said that it isn't a screen issue. From what I understand, by doing a quick search on Google, this is in fact a screen issue. The panic relates...
        Yesterday, 08:37 PM
      • the_rem
        Unknown transformer : how to find a good replacement part ?
        by the_rem
        Hello guys,

        I would like a quite old but still good 800 W ATX PSU to be repaired. The problem was an extremely heavy coil whine coming from the small secondary transfomer on the PCB.

        I desoldered it hoping the references on the upper side would allow me to find a adequate replacement part. Sadly the written references drove me nowhere but to the manufacturer (I-MAG). I sent them a message like a bottle in the see asking them to send me a datasheet of the transformer. And... They responded ! I received a kind of datasheet (see attachment) but my competencies do not allow...
        VEF20FB07BW(2025001A)20110927.pdf
        https://drive.google.com
        04-23-2025, 01:48 AM
      • ezenia
        PS4 controller left stick potentiometer replacement issue
        by ezenia
        Hello,

        Not sure if this is the correct section, but I have a PS4 controller that I am trying to fix. It developed stick drift on the left stick and the usual simpler methods did not fix the problem.

        So I went on eBay and ordered some replacement potentiometers. https://www.ebay.co.uk/itm/174967976757 is where I got them from.

        I took the green potentiometers off the replacement sticks and soldered them onto the PCB. Assembled the controller and ran some tests. The drifting was somewhat fixed (not fully in center, but way better than before). However,...
        09-30-2023, 02:19 PM
      • boosti45
        Macbook pro logic board replacement parts quesion
        by boosti45
        i have a 2020 macbook pro 13" A2251 with 820-09149 logic board so i found an issue with chip labeled U6903 according to schem. boardview using flexBV software, so i removed it from the board and the issue im having is that the chip says "07A08FI ELC180​" on top of it but when searching for a replacement chip, i can find tons of identical looking chips that also have "ELC180" printed on them but the first set of digits is never the same so im trying to find out if i need this exact chip with these same numbers as mine and if not which ones are compatible as a replacement?...
        08-21-2024, 05:23 AM
      • Loading...
      • No more items.
      Working...