When tying a knot solves most of the hum issue!
- Thread starter kodabmx
- Start date
I did that to a speaker wire once, and an EE friend saw it and said I had created a filter.
I took apart a flat screen TV (scavenger hunt) and saw that the mains power lead was looped once through a ferrite cylinder. I did some internet sleuthing and found out that this was a ground loop breaker scheme for eliminating hum. I took it out and used in my preamplifier.
Does it work? Well there's no hum or ground loops. I've made it a point to grab these out of any flat screen I see in the electronic recycle dumpster. I also saw where Mouser and Digi-Key sell these.
Does it work? Well there's no hum or ground loops. I've made it a point to grab these out of any flat screen I see in the electronic recycle dumpster. I also saw where Mouser and Digi-Key sell these.
Indeed, ferrite chokes are good for eliminating certain interferences.
I've got a couple of them clipped around various devices around the house.
Is that cable from a turntable?
Is that green alligator clip jumper your phono ground?
If both are yes, it is proximity between then that reduces ground loop hum.
I wrap my to ground tightly around the tt cables up to the binding post.
Jn
Yes, it's a turntable. Yes the green clip is the ground.
I do know there is a lot of stray power interference in here. AM radio is useless, the entire dial is 60/120Hz.
I almost feel like winging common mode toroidal chokes for them or as mentioned, using ferrite. Still, the hum problem is about 95% gone, and it appears to be somewhat inductive. Moving my DAC several feet away further reduced the hum (it has 3 power transformers in it).
I guess it could be RF. An older design would pick up 98.1MHz FM through the turntable cabling. I guess it was a kind of slope detector.
I do know there is a lot of stray power interference in here. AM radio is useless, the entire dial is 60/120Hz.
I almost feel like winging common mode toroidal chokes for them or as mentioned, using ferrite. Still, the hum problem is about 95% gone, and it appears to be somewhat inductive. Moving my DAC several feet away further reduced the hum (it has 3 power transformers in it).
I guess it could be RF. An older design would pick up 98.1MHz FM through the turntable cabling. I guess it was a kind of slope detector.
It's just simple loop pickup.
Make a better ground. Take the new ground wire, wrap it tightly the entire way around the shielded pairs, then connect at the preamplifier with minimal loop between it and the RCA's.
Then your equipment should be far more impervious to pickup.
Jn
When I set up my turntable, everything went without a hitch!
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