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Projects => General Questions => Topic started by: pgodfrin on January 08, 2021, 10:41:37 PM

Title: Noisy circuit, only when bench testing
Post by: pgodfrin on January 08, 2021, 10:41:37 PM
Howdy Folks,
Is there a way to avoid the RF noises when bench testing a circuit?
thanks,
pg
Title: Re: Noisy circuit, only when bench testing
Post by: alanp on January 09, 2021, 01:49:22 AM
Do you have fluorescent lighting? That can create noise, as can switching-based lights.
Title: Re: Noisy circuit, only when bench testing
Post by: pgodfrin on January 09, 2021, 02:55:13 PM
yep. dang.
Title: Re: Noisy circuit, only when bench testing
Post by: mauman on January 09, 2021, 04:41:06 PM
LED lights too, the "shop light" type hanging over my bench is noisy.
Title: Re: Noisy circuit, only when bench testing
Post by: jimilee on January 09, 2021, 06:43:01 PM
I build
In front of my computer, I don't like to print out Boms. I was testing with my strat one day, and I kept getting a hum, drove my bits. I finally figured it out after 2 hours of mad frustration.


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Title: Re: Noisy circuit, only when bench testing
Post by: mauman on January 10, 2021, 01:26:52 AM
Cell phones!  Not hums, but random clicks and what sounds like bursts of data.  Laid one on top of an amp one day and it took me forever to figure it out. 
Title: Re: Noisy circuit, only when bench testing
Post by: jimilee on January 10, 2021, 02:17:55 AM
Quote from: mauman on January 10, 2021, 01:26:52 AM
Cell phones!  Not hums, but random clicks and what sounds like bursts of data.  Laid one on top of an amp one day and it took me forever to figure it out.
Oh I know man, that makes me nuts.


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Title: Re: Noisy circuit, only when bench testing
Post by: pgodfrin on January 10, 2021, 02:32:38 PM
Yeah the cell phone thing really had me going once at a live recording, pretty much ruined the quiet parts. At first I thought it was a major duty wifi signal, but next time I raised the stand a foot or so higher and it went away!

Anyway in my case, I have both fluorescents AND led... I was hoping there was an easy way to shield the unit or add some noise controlling to the jacks or something like that...
Title: Re: Noisy circuit, only when bench testing
Post by: mauman on January 10, 2021, 06:38:11 PM
Distance from the noise source helps.  Faraday cages have to be really continuous, no gaps, or they don't help.
When I'm looking for noise in a circuit, I turn off the overhead lights and work by the glow of the pedal's LEDs.  I should probably install an incandescent bench lamp...
Title: Re: Noisy circuit, only when bench testing
Post by: pgodfrin on March 06, 2021, 02:11:31 PM
well duh, the soldering iron ! I turn it off and a lot of the noise goes away...