Help with cap spec sheet

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • Retrogator
    New Member
    • Jul 2019
    • 9
    • United States

    #1

    Help with cap spec sheet

    Need some advice on a vintage PC restoration project.

    Trying to replace four axial caps on an AT&T PC6300 (aka Olivetti) backplane board that gassed and corroded the leads. Thankfully, no damage to the board. They are Ace 47uf 25V electrolytics -40 - 80C range (see pic).

    This is an 8088 computer, so can't find the specs for these caps anywhere. I miraculously found a board schematic, but the caps are not depicted.

    I replaced with IC 476TTA025M caps that match the capacitance/voltage/temp specs, but not sure they're working (getting a DMA error on POST which in these old machines sometimes indicates a power rail problem). PSU voltage looks normal. Could be due to another issue entirely, but thought I'd pick your brains about these old cap specs.
    Attached Files
  • R_J
    Badcaps Legend
    • Jun 2012
    • 9535
    • Canada

    #2
    Re: Help with cap spec sheet

    There is nothing special about them, any 47µf/25v axial cap should work Here is a Digikey link https://www.digikey.com/products/en/...=1&pageSize=25

    Comment

    • Retrogator
      New Member
      • Jul 2019
      • 9
      • United States

      #3
      Re: Help with cap spec sheet

      Many thanks. Next step is possible memory parity error. That can cause a DMA 04 error. Fun, fun!

      Comment

      Related Topics

      Collapse

      • Hylax
        Replacement capacitor options please?
        by Hylax
        Hi, I'm super new to this capacitor stuff but I've some basic soldering experience with old cellphones PCBs and headphones. I have this APAQ AR5K 820∆μF 3V Dc Capacitor from a motherboard that I'm looking to replace, photos I've attached. But I'm unable to find a 3V one like I've marked in the spec sheet in red (This is the one currently present in the motherboard). But the 6.3V one I can find (marked in blue) is of similar dimensions but different specs as mentioned in the table. Is it okay to replace it with higher voltage cap, slightly higher ESR, slightly lower ripple current, and double...
        08-09-2024, 11:25 PM
      • jezzaaaa
        Identify replacement diode
        by jezzaaaa
        I'm trying to find a replacement diode for one that has gone short.

        I have a generic USB charger that went short circuit to ground on 5V. I found that one of a pair of identical diodes in parallel (and in series with transformer secondary winding) has gone short in both directions, so I suspect it's bad. The marking is CSRS1045, which I believe is a low barrier Schottky with max current 10A and max reverse 45V. I found a spec sheet for CSRS1045-A that has same specs and also says 350mV drop when forward biased.

        I can't find the exact part number for sale. Similar...
        05-09-2023, 11:26 PM
      • lfhlaw
        60LN5600 white reflective sheet
        by lfhlaw
        So I had to replace the LED lights on this TV and that worked out nicely. But the White reflector sheet that helps to diffuse the led lights evenly was glued into the back chassis which had to be removed to replace the LEDs.

        Placing the white reflector sheet caused it to not sit evenly - causing weird diffusing when TV was all put together. Picture is still decent, but now there are dark and light spots due to the white reflector sheet not sitting against the back chassis.

        Anyone have thoughts on replacement white reflector? or do I just scavenge broken TVs for...
        05-23-2022, 07:14 PM
      • omgitdrifty
        Axial Resistors help
        by omgitdrifty
        Hello all hope you all well
        I just want to make sure I got this right.


        This is 150 Ohms 5% Axial Resistors
        Brown Green Brown Gold
        Please let me know.
        Many Thanks
        David...
        10-04-2024, 08:21 AM
      • howardc64
        A1312 (27” iMac 2009-2011) A1407 (Thunderbolt Display) A1316 (Cinema Display) Display Black Screen Repair
        by howardc64
        Problem

        This is an LG edge LED lit LCD Display. The LEDs are on the bottom edge of the display. There are 2 bars (left and right) Each bar has many LEDs and a 6 pin connector. Each pin drive several LEDs thus is the highest current flow / heat junction. The weak lead free solder gradually fails with thermal expansion/contraction cycling and increases resistance. PSU will compensate up to a point, then when the current is too high, PSU just shut down the backlight causing a dark display. I have even seen one which the connector just fell off as solder points became completely detached....
        08-04-2024, 10:36 PM
      • Loading...
      • No more items.
      Working...