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Tube amp - electrostatic shielding beneficial?


2014-08-29 8:11 am
I'm about to start requesting quotes from transformer manufacturers for my DCPP mono amp. It will be a C-core or EI type power transformer to match my output transformers.

When getting a custom power transformer built how beneficial is electrostatic shielding? Also, I have read comments that an electrostatic shielded transformer needs to be properly grounded. Is it as simple as connecting it to the PCB ground? I don't think the original Hammond 290FX has a electromagnetic shield.

Ground Connection.JPG

I'm already aware of the benefits of external shielding with a copper flux band. And I will be requesting that.
Electrostatic or electromagnetic shield? Internal traffo shield is electrostatic barrier (A less than a turn not shorted, and sent to an independent wire to be grounded, deriving to ground the capacitive coupling inside the traffo. But the magnetic shield may be an external shorted turn around all the code. CC cores surely will not need it. Try and chime us.


2006-04-17 6:27 pm
This shield would go round the primary, shielding secondaries from mains hash and is connected to chassis ground. I've never found a profit in it.
The copper band round the mains transformer otoh should work well with close spaced transformers and/or high sensitive circuits needing the extra shielding.


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