Strange 5534 thermal shutdown

When you used the FC caps, did you use them in a bipolar arrangement or just single?

EDIT: also, was anything hooked to the outputs when you were doing the testing?

When you used the FC caps, did you use them in a bipolar arrangement or just single?

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Not sure what you mean? C102/C106/C202/C206 are Panasonic SU, C105/C205 are Panasonic NHG. I never tried different ones, as I wanted them to be bipolar or as small as possible. I measured the (single) FC just for reference and to make sure that my DVM is not measuring crap.

Was anything hooked to the outputs when you were doing the testing?

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I tested both with and without load (a tape desk). No difference. PlugIn-power on/off doesn't matter either.

Samuel

[quote author="Samuel Groner"]

But what was the impedance to ground at the n.i. input to begin with?

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The PADs are 10k+1k shunt if out and 10k series/1k shunt if in.

A 1k to ground is brutal, and is attentuating and loading down the mic capsule something fierce.

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I don't like it either, but I didn't want to try several values, so I just used one that will work. However, one would still think that 11k should be well enough, but it's not.

how can the R101/C101 node sit at zero volts? Aren't you pulling up on a FEt drain in the electret capsules?

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PlugIn-power is switchable.

Samuel[/quote]

So...you are saying that you didn't have the problem when the pad was engaged, i.e., with the n.i. input tied to the 10k/1k junction?

oh i thought you meant that you took out the bipolars and put in the FCs instead.

So...you are saying that you didn't have the problem when the pad was engaged, i.e., with the n.i. input tied to the 10k/1k junction?

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Yep. Did realise that pretty late, though.

Samuel