Magnetic fullwave rectifier.

[Peterae]

Wow look at this i found on ebay, unfortunately it already sold in July for $598


Link here
http://www.ebay.ca/itm/401319476305?rmvSB=true

Description: Up for sale is this very interesting and rare (could find nothing like it on the internet) full wave magnetic rectifier with a patent date of 1916 on the spec plate.  Tesla patented magnetic rectifiers in 1889 to convert AC electric current to DC current.  This rectifier has an old porcelain base light fixture attached many years ago.  It comes with an Edison light bulb.  Base of the piece is cast iron with copper coil in center, original amp meter and switch plate.  Old wire is not functional and left for effect...I have had this re-wired with modern 18 guage electic cord and thumb switch to turn the light on or off.  A hundred year old piece with a great look from the Tesla and Edison era of early 20th century.  Will make a great accent piece not to mention good night light.

Dimensions:  Base measures 9" X 5" and stands 7" to the top of the light socket.

PS I dont think this was made by Tesla but as he was the inventor of the magnetic rectifier i thought it relevant, so far i have not been able to fully read the tags to see which patent is referred to.

[Smudge]

Could be US000413353 - N Tesla - Method of obtaining direct from alternative current - 1889
Smudge

[Peterae]

yep looks good, although the only thing puzzling me is how can you have full wave rectification with only one core in the above device.

I am thinking it would be pretty cool to use a neo magnet to bias a core close to saturation to form a magnetic diode and see how it performs, it's going to be difficult to match the magnet strength to the correct core, although the iron bundle used in the above device can be adjusted by adding or removing iron.

As this is your area of knowledge how hard do you think it would be to match a neo magnet to a known ferrite cores saturation, i imagine it's just a matter of looking up data sheets and matching the 2?

I wonder what the upper frequency could be, and am wondering if it would be possible to directly rectify a broadband signal from an aerial without the diode junction bias voltage.

[Peterae]

I found someone else asking for info in 2002

https://www.smokstak.com/forum/showthread.php?t=15149

1916 Magnetic Rectifier - Info?
Ok you expert "Ark'rs", how many of you have seen one of these or have one in your collection. I have had this one for about four years now and I have "attracted" two more.

The tag says: Full Wave Pat'd 1916 - Magnetic Rectifier - Volts/110 - Cycle/60 ----- Charging Circuit - Volts 6 - Amperes 7 - Type 16. The France Mfg. Col. Cleveland, Ohio U.S.A.

I'm looking for any literature or manuals for these things. I have "restored" this one and it works well.

Thanks for any assistance on this.

"DELCO DON" Southern Illinois

This led me to look for the manufacturer, they made battery chargers
Here's a type 6
http://www.radiomuseum.org/r/france_full_wave_rectifier_f_f_type_6.html

EDIT
OK i found the patent 18 Apr 1916 to Lester E France hence the France Mfg company
https://www.google.co.uk/patents/US1179515?dq=rectifier+Cleveland&hl=en&sa=X&ved=0ahUKEwjb5ozu7onWAhVBJVAKHQSFAYMQ6AEINDAC

Not had a chance to read it yet

[Smudge]

So it's a clever piece of electro-mechanical engineering using electrical opening and closing contacts driven magnetically from the 60 hertz input.  Nothing exciting there.
Smudge

[Peterae]

Hi Smudge

Indeed, i have had a chance to look the patent over and it is indeed exactly as you say and nothing to do with Tesla shame, i will probably just delete this thread, but i do think it would be worth building a true Tesla rectifier biasing a core to saturation so we get rectification when we drive the core below saturation.

[Smudge]

Hi Smudge

Indeed, i have had a chance to look the patent over and it is indeed exactly as you say and nothing to do with Tesla shame, i will probably just delete this thread, but i do think it would be worth building a true Tesla rectifier biasing a core to saturation so we get rectification when we drive the core below saturation.

The problem there is that the biased core creates a rectified magnetic waveform, not a rectified electric waveform.  A series of magnetic half sine waves does not result in a series of electrical half sine waves because the voltage is the time differential of the former, and that does not produce DC.
Smudge

[Peterae]

Right i understand the problem now, oh well thats put that to bed anyway,

Thanks  Smudge