[Amps] Here's a Shocker

[Will Matney]

Isn't the natural frequency for nervous system about 40 Hz? I remember 
talking to a guy who was investigating the use of electromagnets to help 
with healing, and if I remember correctly, he said it was at 40 Hz. I 
can't remember to be honest, does anyone know?

I could see raising the frequency up a bit, maybe up to 80-100 Hz. That 
would in fact drop down the size of power transformers but the conductor 
size would be the same. You would really only save some on the amount of 
iron. I don't think that would be enough frequency to increase the skin 
effect that much (raise the conductor size). The main thing is steering 
clear of the nervous system frequency or a harmonic thereof. In power 
transformers, increasing frequency drops the core size but may increase 
the conductor size due to the skin effect. However, the skin effect 
doesn't really come into play except in the higher frequencies above 
maybe 100 KHz or so I don't think. The reason being is, I've never seen 
any increase in wire size for audio transformers, as compared to power 
transformers. Most inverter/converter circuits run at 400-1200 Hz and 
some more modern ones more than this. One must remember though that the 
waveform is a square wave in inverters. This in turn changes the core 
size somewhat from a sine wave (X 1.11).

Best & 73's

Will Matney




John Lawson wrote:

>
>
>   Usually I try to snip replies - but all this is relevant:
>
>
>
> On Mon, 15 Nov 2004 Dennis12Amplify at aol.com wrote:
>
>>
>> In a message dated 11/13/04 9:40:48 AM Central Standard Time,
>> dezrat1242 at ispwest.com writes:
>>
>> Which makes me wonder if it  wouldn't be good to have our AC power
>> lines run at about 1000 Hz or  so.  No more shocks, no more accidental
>> electrocutions.  The  worst that could happen would be a burn.
>> Something to think about,  eh?
>>
>> I know the arguments against it - transmission loss being the  most
>> significant - but someday when houses have their own little  nuclear
>> generators and are "off the grid" it might be something to  consider.
>>
>>
>> ---------------------------------------------------------------------------- 
>>
>>
>>
>> Actually, the power transmission would be much more efficient as the
>> transformers and capacitors could be made much smaller.
>>
>> Regards,
>>
>> Dennis O.
>
>
>
>   With all due respect, and purely out of regard for your personal 
> safety, I *STRONGLY* suggest that both you gentelmen immediately 
> suspend all involvement with these items until you gain a better 
> understanding of basic AC theory and practice!!
>
>   In the first place, the adverse physiological effects of voltage on 
> the human body is due mainly to currents above a certain threshold 
> across the chest cavity and heart structures, clamping and spasm of 
> muscles resulting in tearing of tissues, and nerve 
> damage/eradication.  Then there are the burn phenomena, both resitive 
> and RF induced.
>
>   These come into play at various points and severities, depending on 
> the amount of current dropped by the body, the path taken by the 
> voltage, and the frequencies (from DC to RF) as well as the voltage, 
> and the duration of the exposure.
>
>   Y'all *really* oughta read up on some basic electrical and RF safety 
> - I'm sacred for you.  I've lost friends in electrical accidents and 
> it's not the prettiest way to depart the planet.
>
>   As for power transmission being more efficient at higher line freqs: 
> look up "skin effect" and see how that tallies with your theory. High 
> frequencies travel more and more on the the surface of a conductor - 
> which is how microwaves use 'waveguide' (very basically).  Many times 
> you will see big HF coils wound with tubing - no use having all that 
> copper if it'll never see the currents.
>
>   Aircraft used to use 400 Htz to cut down on the iron/copper wieght - 
> but the most modern ships are all going to DC busses as the gear gets 
> smaller and more integrated.
>
>   Please do get a btter idea of these safety issues before you find 
> out the hard way.
>
>  Cheers
>
> John  KB6SCO
> _______________________________________________
> Amps mailing list
> Amps at contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
>
> __________ NOD32 1.880 (20040928) Information __________
>
> This message was checked by NOD32 antivirus system.
> http://www.nod32.com
>
>
>