Tests of the Jeff Cook's device
created on October 2, 2003 - JLN Labs - Last update October 8, 2003
Toutes les informations et schémas sont publiés gratuitement ( freeware ) et sont destinés à un usage personnel et non commercial
All informations and diagrams are published freely (freeware) and are intended for a private use and a non commercial use.

The purpose of this experiment is to test and check the Jeff Cook's Effect. The full diagram of a proof of concept device has been released to the Internet on September 23, 2003 in the document " Designs for Generating the Jeff Cook Effect" by Jeff Cook from D-Labs. The inventor claims that a flame bends towards or away from a specially constructed coil powered only by a 9 volt battery.

Above : The original experiment done by Jeff Cook.

The full details of the experiment and some original photos of the main test conducted by the inventor can been found at :

You may download the full detailled document : " Designs For Generating the Jeff Cook Effect " by Jeff Cook


So, according to the main Cook's paper, I have tried to replicate the device. Below, the design of my tested device :

Above, some photos of the different coils and parts used for building the Cook's device

Above, the Jeff Cook's device is now ready for testing...

Tests results ( 10-02-03 ) :

Unfortunately, when the Cook's device is energized, I haven't been able to see any motion of the candles flames placed in front and behind of the main axis of the Cook's coil ( see the photos below )... Various coils polarities have been tested ( additive and substractive B-Field fields ), no significant change have been observed. The Cook's device have also been tested in a range between 9 to 18 V DC. I have noticed that the working frequency change with the input voltage.

Notes from Jean-Louis Naudin : In spite of my unsuccessfull tests result, this is only my first attempt of replication, may be that some components that I have used are a bit different from the original design built by Jeff Cook himself. I need to conduct more tests and improvements on my device. The next test run will use 400 m of steel wire 0.7 mm diameter ( zinc coated ) for the flower coil.

TEST RUN #2 ( 10-03-03 )

For this test run #2, the power coil and the flower coil have been removed. The previous flower coil has been replaced with 400 m of steel wire 0.7 mm diameter ( zinc coated ) from four coils of flower wire, then the initial power coil has been replaced again.

Tests results :

Unfortunately, when the device is energized, the flame of a lighter is not bent in front and behind of the main axis of the Cook's coil ( see the photos below )...

Clik here to here the sound of the switch relay of the Cook's device ( at a working voltage : 10 V DC )

TEST RUN #3 ( 10-06-03 )

After the test run #2, I have received a comment about my tested setup from Jeff Cook himself :

" Jean-Louis,

I notice from the photos that you are NOT using a hollow core.  This is one of the most important features, as mentioned many times.  I see a solid bolt in one photo and a wood dowel in another.  This would easily explain why you have received no results. 

In any case, thank you much for your attempts and all the time you've spent on this.  I will await others to complete their device...to spec.

Jeff "

So, following the Cook's advice, I have completly removed the wood core from the flower coil so as to get a FULL HOLLOW CORE...

In this test, the Flower coil uses an FULL HOLLOW CORE...

The flame of the light is not bent while the Cook's device is powered...

Notes from Jean-Louis Naudin : Today, on October 6, 2003, I have not been able to replicate myself the Jeff Cook Effect. Thanks to Jeff Cook for the sharing of this experiment through the Internet.

I hope that some other experimenters will soon succeed in the replication of this experiment... Please, don't forget to keep me informed in the case of you succeed.

Reference documents :

For more informations :
Email : JNaudin509@aol.com

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