[photo-3d] Re: unsafe FEDS (was converting a Fed Projrctor)

[Peter Homer <P.J.Homer@xxxxxxxxxxxxx>]

Sorry for the late reply to Mike Canter's post

>In Digest 310 P.J. Homer writes, in part:
>
><<  I believe what led
> to the ban was a general EEC (European Economic Comunity) directive from
> Brussels on electromagnetic field outputs.  >>
>
>
>Excuse me?  Did I read that correctly?  EMF emissions?  Has anyone 
>studied our beloved vintage TDC's & etc.?  What are the mortality rates 
>for projectionists vs. the general population?
>
>And they say cell phones are bad...
>
>We're all gonna die!

My Email has been down again for a few days. I believe I first got the information from this group,provided by Tony Shaps of the Widescreen Centre they briefly carried the Fed Camera and projector until the projectors importation was banned by the EEC. The EEC is notorious for bureaucratic over reaction and many devices built even immediately before the ban would fail,I am not shure if the ban applies to second hand goods as well but there are other regulations concerning the sale of second hand mains equipment. I have not stopped using my Fed because of the ban and do not intend to do so, the levels being investigated  at 50 hertz are 12 kilovolts per metre for electic and 1.6 milliteslas for magnetic fields. Domestic appliances are only measured in microteslas but there is probably a limit to these as well because of the accumulative effect.I tested mine with a Hall probe which dont usualy work on AC but this one does with reduced sensitivy. The frequency response fall by 3a!
ts (down 70%) at 500Hz on the 10
0mT range and 50Hz ( British mains frequecy) on the 10mT. With 50Hz through a coil the relative output changes by about 7:1 and not 10;1 when switched from 10mT to 100mT. Perhaps because of this I could detect nothing from my Fed even on the 10mT. I was able to get a reading with a 500 turn search coil conected to an ameter but I was unable to relate that to Tesla. This reading was obtained from 
the motor side of the case, not the dissolve circuitry which many people thought would be the culprit and a motor should be installed in all projectors. Oddly I have failed to repeat this reading and my one remaining Fed which I now removed the dissolve circuitry from and converted to 24 volt no longer gives a reading suggesting the dissolve circuits were responsible after all.  P.J.Homer