[time-nuts] Lead acid battery noise levels

Bruce Griffiths bruce.griffiths at xtra.co.nz
Tue Jul 9 08:54:47 EDT 2013


David Kirkby wrote:
> On 9 July 2013 04:52, Mark Spencer<mspencer12345 at yahoo.ca>  wrote:
>    
>> Hello, I've just reviewed the thread from earlier this year regarding low noise power supplies and some related information about the noise levels of certain batteries.    Has anyone ever come across any data pertaining to the noise levels of common gelled lead acid storage batteries ?
>>      
> Have you come across the volt-nuts list?
>
> https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
>
> I see a bizzare review of an HP 3457A meter on utube
>
> http://www.youtube.com/watch?v=HfxpJCdgVwc
>
> where the guy determines the noise level of the 6.5/7.5 digit meter by
> measuring the voltage of what he describes as a "general purpose lab
> power supply". Is it me, or is it a bit dumb to try to "measure" the
> noise level of a laboratory multimeter by using a general purpose lab
> power supply.
>
> I must admit, I thought that using a battery would have been stable at
> least short term, but it seems there is noise on a battery - something
> I was not aware of until today.
>
> Dave
> _______________________________________________
> time-nuts mailing list -- time-nuts at febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>
>    
A battery is noisest when current is flowing in the battery.
With no current flow (or electrolyte disturbance) the noise is very low.
NIST has measured the noise of unloaded NiCd cells for example and it is 
extremely low.

Bruce


More information about the time-nuts mailing list