[RFI] Noisy PC Speakers

[K9MA]

Perhaps because the speaker wires were acting as a counterpoise, and 
actually increasing the conducted emissions on the power leads. Did you 
try a common mode filter on the power leads when the speaker leads were 
connected?

73,
Scott K9MA

On 10/5/2020 1:00 PM, Hare, Ed W1RFI wrote:
> < Second, every wire/cable connected to a noise source (in this case, the Class D amplifier, but also including switch-mode power supplies) forms a transmitting antenna for common mode current on those wires. So nothing in your lab tests is surprising.>
>
> Actually, it is very surprising, at least to me, because when we changed the nature of the speaker loads, the conducted emissions on the AC mains increased.


-- 
Scott  K9MA

k9ma at sdellington.us