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  • Re: Capacitor rules

    From Wanderer@21:1/5 to John on Mon Jul 8 09:50:48 2024
    John wrote:
    I tap electronic tubes to see if they are good, but you say he tapped >capacitors? Electrolytics I guess, might show issues when tapped, like
    poor internal connections.

    Interesting hadn't really thought of that as a test for caps...

    John :-#)#

    I used to press the tops of old electrolytic capacitors. When they were
    bad they would pop up like the safety lid on food jars after you open
    them. Maybe they get soft on the sides on too.

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  • From Martin Brown@21:1/5 to Wanderer on Tue Jul 9 17:27:40 2024
    On 08/07/2024 09:50, Wanderer wrote:
    John wrote:
    I tap electronic tubes to see if they are good, but you say he tapped
    capacitors? Electrolytics I guess, might show issues when tapped, like
    poor internal connections.

    Interesting hadn't really thought of that as a test for caps...

    John :-#)#

    I used to press the tops of old electrolytic capacitors. When they were
    bad they would pop up like the safety lid on food jars after you open
    them. Maybe they get soft on the sides on too.

    Electrolytics that have outgassed internally can have a fair bit of
    pressure internally and take on rakish angles as the base expands. They
    smell horrible if they go pop when hot.

    --
    Martin Brown

    --- SoupGate-Win32 v1.05
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  • From legg@21:1/5 to Wanderer on Wed Jul 10 07:54:06 2024
    On Mon, 08 Jul 2024 09:50:48, Wanderer<[email protected]> wrote:

    John wrote:
    I tap electronic tubes to see if they are good, but you say he tapped >>capacitors? Electrolytics I guess, might show issues when tapped, like
    poor internal connections.

    Interesting hadn't really thought of that as a test for caps...

    John :-#)#

    I used to press the tops of old electrolytic capacitors. When they were
    bad they would pop up like the safety lid on food jars after you open
    them. Maybe they get soft on the sides on too.

    Knocking can be done with an isolated object, like a screw diver
    handle. The intention is to initiate any kind of intermittent
    behavior, quickly.

    'pressing' implies burned - zapped teckies.

    Be smart. Be safe.

    RL

    --- SoupGate-Win32 v1.05
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  • From Jan Panteltje@21:1/5 to [email protected] on Wed Jul 10 12:47:25 2024
    On a sunny day (Wed, 10 Jul 2024 07:54:06 -0400) it happened legg <[email protected]> wrote in <[email protected]>:

    On Mon, 08 Jul 2024 09:50:48, Wanderer<[email protected]> wrote:

    John wrote:
    I tap electronic tubes to see if they are good, but you say he tapped >>>capacitors? Electrolytics I guess, might show issues when tapped, like >>>poor internal connections.

    Interesting hadn't really thought of that as a test for caps...

    John :-#)#

    I used to press the tops of old electrolytic capacitors. When they were
    bad they would pop up like the safety lid on food jars after you open
    them. Maybe they get soft on the sides on too.

    Knocking can be done with an isolated object, like a screw diver
    handle. The intention is to initiate any kind of intermittent
    behavior, quickly.

    'pressing' implies burned - zapped teckies.

    Be smart. Be safe.

    If you have an oscilloscope and if it are supply filter capacitors,
    just look for any RF spikes and excessive ripple on those.
    And often bad filter caps have a swollen top.

    And make sure your scope is insulated from ground if you scope around in say an old mains connected TV set
    and take care you are insulated from ground too.
    Or use a mains insulation transformer.

    I bought a new Samsung color TV a while back,
    to my surprise a 2 ping mains plug, no ground pin.
    I was reading Samsung workers are on strike..
    Their current leader was in jail, they should have kept him there.

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