Re: coherers

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Antonio Carlos M. de Queiroz by way of Terry Fritz <twftesla-at-qwest-dot-net>" <acmq-at-compuland-dot-com.br>

Tesla list wrote:
> 
> Original poster: "Ed Phillips by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<evp-at-pacbell-dot-net>

>         What about eddy current losses?  Don't the turns make contact
with each
> other?

Maybe. A kind of litz wire would be desirable.

>         Sounds like a VERY valuable antique.  The last one I saw for sale
went
> for $4500 U.S., and had none of the features you mention.  Marconi
> collectors are willing to pay an unbelievable amount for Marconi
> antiques, more than $25,000 at a recent auction.

The staff of the museum looked quite impressed when I told them.
The two devices are exactly these:
http://www3.bc.sympatico.ca/radiomuseum/maggie.jpg
http://www.faradic-dot-net/~gsraven/fons_images/Page_2/MAG_DET.jpg
(Without the little handle in the pulley)
http://www3.bc.sympatico.ca/radiomuseum/tuner.jpg
http://www.faradic-dot-net/~gsraven/fons_images/Page_2/marctune.jpg
There is a schematic diagram here:
http://home.luna.nl/~arjan-muil/radio/marconi/marconi-system1.html

Antonio Carlos M. de Queiroz