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  1. Replies
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    Yes, that's what I originally bought them for....

    Yes, that's what I originally bought them for. But with high speaker currents I wouldn't want to rely on some press fit grounding.
    So they are useless.
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    I can confirm that the 2 RCS plugs have NO...

    I can confirm that the 2 RCS plugs have NO solderable ground lugs/tabs (at least the two I once bought). The body is a single massive piece of metal (probably nickel plated cast zinc). It doesn't...
  3. Looks as if the author is a certain T(im)Robbins...

    Looks as if the author is a certain T(im)Robbins :)
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    Peak PI output is actually less than 1/4 HT.

    Peak PI output is actually less than 1/4 HT.
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    Pictures? I'd start with warm soapy water on a...

    Pictures?

    I'd start with warm soapy water on a cloth.
    If that's not enough use some oil (or WD-40) on a cloth (after drying) and (carefully) follow up with naphta or white spirit - or soapy water...
  6. "Panning" between out of phase signal versions...

    "Panning" between out of phase signal versions produces phase modulation. And phase modulation always means frequency modulation as well. The frequency shift is proportional to the rate of phase...
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    Yes, but the OP's question was about leakage. And...

    Yes, but the OP's question was about leakage. And only the leakage test requires high voltage (could be taken from the amp).
    The importance of real cap value (as opposed to DMM cap measurement) and...
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    The simple setup described in posts #12/13 is all...

    The simple setup described in posts #12/13 is all you need to measure leakage.
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    Sorry, I misinterpreted. As Rg1-k is specified as...

    Sorry, I misinterpreted. As Rg1-k is specified as a max value, any lower value is fine with the KT88s. And a lower source impedance is able to drive a lower load impedance. So no problem with halving...
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    I can't think of a reason why the static field of...

    I can't think of a reason why the static field of a bigger speaker magnet should give rise to feedback.
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    Grid leak means a DC path between grid and...

    Grid leak means a DC path between grid and cathode. Lowered AC source /PI impedance doesn't matter.
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    Don't forget that chlorine is a gas. It...

    Don't forget that chlorine is a gas. It evaporates and then attacks and corrodes most everything. Sometimes the damage shows after years.
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    Chlorine is one of the most aggressive and...

    Chlorine is one of the most aggressive and corrosive chemical agents. It seems counterproductive to fight corrosion with a highly corrosive substance.
    The tiniest residue may cause a lot of long...
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    OTs having specs of 50/60W and a primary...

    OTs having specs of 50/60W and a primary impedance of 4k to 4.5K are very common for 2x 6L6 amps with a B+ of around 450V.
    I guess it would work but the lower impedance will cause excessive plate...
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    Well if a measurement with 9V gives a leakage...

    Well if a measurement with 9V gives a leakage resistance below 500k, the cap is definitely bad.
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    I think you meant 1V across the 1M corresponds to...

    I think you meant 1V across the 1M corresponds to 1ľA.

    According to ecap manufacturers' (Epcos, Nichicon) recommendations, the reforming current can be up to 5mA and the recommended series...
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    1) 2k2 is the proper cathode resistor value. 220R...

    1) 2k2 is the proper cathode resistor value. 220R cause very hot biasing, low plate voltage and poor tube operation.

    2) Assuming the new Celestion speaker gave rise to the feedback issue, you...
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    You'll get a negative reading (reverse current)...

    You'll get a negative reading (reverse current) if the cap is still charged to a higher voltage than your (meter) battery. Always make sure that the cap is completely discharged.
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    Regarding OT specs, the 7027A datasheet suggests...

    Regarding OT specs, the 7027A datasheet suggests a ~70W OT with a primary impedance of 6k to 6.5k.
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    Not clear what other side means. If you reversed...

    Not clear what other side means. If you reversed meter leads you put wrong polarity voltage on the (still charged) cap. Wrong polarity voltage can damage the cap.



    It's more or less the same...
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    What happens if you disconnect the OT CT from...

    What happens if you disconnect the OT CT from point A?
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    To see if a cap passes DC (no good) you best use...

    To see if a cap passes DC (no good) you best use your Ohmmeter (2M range or higher). Disconnect the cap from everything, discharge and connect your red meter lead to the positive cap terminal and the...
  23. I read the thread and think it wasn't quite clear...

    I read the thread and think it wasn't quite clear what the loaded PT secondary voltage was.
    And it's not clear if the 2x290Vrms quoted here is PT spec or measured value.
    Exact values will depend on...
  24. To avoid the redplating tube dissipation must be...

    To avoid the redplating tube dissipation must be reduced. This can be achieved by either lowering B+ (e.g. by increasing the sag resistor) or by lowering cathode current (increasing cathode resistor...
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    These are electrical contacts and the best...

    These are electrical contacts and the best treatment for contacts is Deoxit and Q-Tips or a toothbrush.

    Acids like vinegar tend to activate new corrosion.
  26. For a given tube type redplating solely depends...

    For a given tube type redplating solely depends on tube dissipation. So with same cathode current and voltages all amps/circuits will make the EL84s redplate when plate dissipation exceeds around 14W.
  27. What do you mean with OG? Does that mean...

    What do you mean with OG?



    Does that mean that there is a voltage difference of 13V between 2 chassis ground points? This would mean bad contacts and a safety issue.
    (Regarding amp voltages...
  28. THe obvious difference is the higher value (750R...

    THe obvious difference is the higher value (750R instead of 470R ) dropper resistor between the first and second filter cap. But that would only lower your screen voltage by around 4V. I don't think...
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