Power cord with built-in inductors?

Not quite but almost, more a mismatched load. Difficult situation, can't reveal too much. In the room it's all legit but we need to muffle at or near the power plug.

So this is an intentional radiator?

RL

On Fri, 18 Mar 2016 17:51:05 -0500, legg Gave us:

Audiophool line cords

What about a small 1:1 transformer? The high frequencies dont propagate that well across the core.

Cheers

umeroUno:

looks like the usual clamp on ferrites, plenty to choose from if they will do the job

-Lasse

They don't, you can't even remotely get to 10uH. Unless you stack half a gazillion clamp-ons in a row.

We need to ferry over a few hundered watts, too big.

serNumeroUno:

s:

is

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toroid ?

-Lasse

Transmission method? If it's clear field, there's not a hope without sheilding all line cords, not just this one.

RL

Have you looked into active EMC?

You still need an Y capacitor, but that can be small Even smaller if you boost the voltage to the driver for the y cap

Cheers

Klaus

Correction.

If you couple to both lines, then you can do it with X capacitors instead which will be a huge advantage

Cheers

KLaus

On Fri, 18 Mar 2016 23:58:43 -0700 (PDT), Klaus Kragelund Gave us:

Wow... Just like 'noise canceling headphones'.

Yes. Active emc is limited by the bandwidth of the current sense and the driver. So best at low freq

Cheers

Klaus

I know but it all has its limits and shielding alone won't help. I know that choking at the power plug does help because we tested it. I am just looking for a cord with the choke or inductors built in because neither marketing nor customers will like a cord with a box flopping about like what power washers have.

Tried it, not enough. Unless you place 20-30 really fat ones in a row.

Wow, I am surprised this sailed through the patent examiner. It's essentially like the old Q-multiplier trick, lots or prior art. But anyhow, feed-forward is not possible in this case because the amount and phasing or coupled RF changes with the position of gear in the room. So the circuit would still have to be at the wall plus and then we might as well place a choke there (because we know that works well).

Tried it, not enough. Unless you place 20-30 really fat ones in a row. ==================================================================================

Can you put the entire power supply in a wall wart? That way you can do whatever you want/need to keep the stuff out of the wires to the wall wart or to clamp it at the wall since now all of that is after the supply and won't affect the ac line input specs, and it's no more painful than a box of inductors at the wall would be and probably easier to "sell" to the client.

----- Regards, Carl Ijames

Yes,it seems very strange this patent was appointed. But I have seen simpler prior art designs that got through the system

Ok. So you are dealing with radiated noise and you cannot wrap an active compensation filter around that? Either long lines or layout with antennas. Because if it's purely conducted it should be able to use active filter

Cheers

Klaus