In article . com,
RHF wrote:

My last visit to Oakland had some hours had a
S9 Noise Level across the Bands below 10 MHz.

My next door neighbors kids had a Band practicing
in their backyard garage. Their Amps and Equipment
were the Source.
* Three Reversed Two Prong {Only} Electical Outlets
plus they were using a Power Strips with the Round
Pin Cut-Off - Rewired the Outlets with Three Prong
Receptacles and gave them two new Power Strips.

Yow, bucking for the Darwin Award, sounds like. What is
it with some of these music dudes...

I'd suggest some GFI power cords, like they use for power
tools, but it sounds like, given the state of their equipment,
that they'd probably bin them the second or third time they
tripped. (The GFI breaker, not the musicians).

* Installed Snap-On Ferrite Cores (10+) on all the
Power Leads and Equipment Cables.

What brand, or, where do you get them?

This dropped the Noise Level down to below S3.

Mark Zenier
Googleproofaddress(account:mzenier provider:eskimo domain:com)