Tesla Patent Apparatus for Transmission of Electrical Energy

[Peterae]

does anyone think it would be interesting to try and build a transmitter and receiver system based on this patent

[pdf]http://www.overunityresearch.com/index.php?action=dlattach;topic=1211.0;attach=6614[/pdf]

[Peterae]

OK so the secondary wire length is 1/4 of the desired wavelength, he is suggesting using 925 Hz which he says is most suited to drive electrical motors and he uses a wire 50 miles long.

Anyone know why he would choose 925Hz as an example.
50 miles is dam long for a secondary winding, i am not sure i fancy winding one this long.

If i use 35 SWG copper enamelled wire then i can get reels that have 1850 meters of wire on them, if i were to use one of these for my secondary then
4 x 1850 gives me a wavelength of 7400 meters or an operating frequency of 40.5405 KHz

now my home and works are 6.94 KM distance apart, this is where i would ideally setup a transmitter and receiver so maybe it be beneficial to adjust my operating frequency to 6940 metres?

Borderland used basket weave construction,the patent does not say anything about this so do i need to basket weave or not?, they use Teflon coated silver coax wire, this is not possible for me so will using copper enamelled wire be OK?

How can i be certain that i use the same length of wire on each coil, i don't think measuring it as i wind is going to be that accurate, and i don't think counting turns is going to be that accurate, maybe i should weigh the copper wire on the spools to see if they are the same and then just hope i get pretty close, maybe it will be possible to tune the coil by cutting the wire down in length once both coils are wound.

So the points i need to work out
Basket Weave Yes/No
Silver Wire Yes/No and is Copper enamelled wire OK Yes/No
Adjust wavelength to the distance of the transmitter and receiver Yes/No
Is it easy for me to adjust the wire length once wound Yes/No

[Peterae]

[2] "Skin Effect", Nick Wheeler, Electronics World, Sept 1997. p780-781.
Discussion of skin effect in audio and RF cables. Silver plating starts to be useful at about 1MHz.

so at my operating frequency it looks like Silver is not needed Silver NO
Basket Weave for reduced inter winding capacitance and higher Q YES
Copper Enamelled wire NO would be better using Litz. This could be expensive though so the question now would be does it make a lot of difference at 40KHz

[poynt99]

Nice page on basket weave etc. coils:

http://www.pa2mrx.nl/UK/coil%20homebrewing_uk.htm

[Peterae]

Hi Darren
Indeed i have looked over a few web sites including that one, they are amazing.

[BEP]

I wouldn't worry as much about the skin effect as I would the proximity effect.

From the photos I've seen Tesla knew of this as he always seemed to have some space between turns on his planar coils.

[Peterae]

I have ruled out the need for silver wire due to the low frequency i will aim for, but because of the length of wire i cannot have much spacing between each coil otherwise it would end up huge, best i can do is basket weave the spiral wind.

the other thing that is puzzling me is that Borderland used a cap across the primary for tuning but Tesla does not in the patent.

how did Tesla tune his primary or know how many turns to use, or are we looking at transformer action here as opposed to resonant tuning action.

[BEP]

The basket weave approach will minimize the proximity effect.

I believe the Tesla system used the capacitance between transmitter and receiver as part of the tuned circuit. In many cases he used the firing frequency adjustments of the spark gap or rotation speed of the rotary generator to control frequency.

Don't forget, this system is not supposed to rely upon Hertzian waves.

[Peterae]

Thanks WW

The basket weave approach will minimize the proximity effect.

Yes this is what i was thinking  

Wow

capacitance between transmitter and receiver

in my case that will be 6.94 Km of chalk and clay not to mention a hill which will probably kill any chance i have   Ah just realized you probably mean the atmospheric connection

Only one way to find out i guess, it will be fun building 2 of these coils  

One thing i did glean from Borderland, if a current meter is placed in series with the earth connection and the secondary, when driving from a Sig gen i should see first a peak in current and then a much larger peak in current as i progress scanning up the frequency, first peak is Hertzian, seconds peak is Longitudinal

One other thing the transmitter coil and receiver coil are meant to be wound in opposite directions, but that is the same as flipping one over surely LOL

[ion]

Hi Peterae:

If I may, I would like to recommend the use of large globes to terminate your coils to the air. You can use cheap cardboard world globes sprayed with a conductive coating. I don't recommend trying to wrap them in aluminum foil, as there will be too many sharp corona points formed.

You want to minimize corona discharge and maximize capacitive coupling to the air. The conductive surface of the globes should be as smooth and clean as possible, no sharp points.

Regarding the basketweave coils, nice site posted by POYNT. One interesting observation is that the Hendershot coils do not seem to obey the standards for conventional basketweave winds, as the radii are much tighter than normal, making almost a half circle before reversing.

Best of luck with your experiment.

P.S. On the Nick Wheeler article, how were you able to obtain that piece?  I have been a subscriber to EWW since the early 70's, but sadly had to drop it recently as the cost became outrageous. I would like to see if it is worth resubscribing if anyone has a link to recent issues.

I still regard EWW as one of the finest publications for the electronics professional / home builder / experimenter and I still have all of the old issues back to the '70's, but became discouraged when their management and content changed dramatically around 1997.

[Peterae]

Thanks for the advice ION

Yep i came to the same conclusion about the termination balls, i have not worked out the how yet, i guess they need to be as shiny as possible as well, i was going to use aluminum paint but this would be dull, i need to look and see if copper paint is available and maybe try polishing it up afterwards, there must be a place to buy stainless balls but probably expensive, i need to look at that a little more yet.

The Nick Wheeler was just a quote at the bottom of an article so i don't actually have the article in question only the posted reference.

[tao]

I know the shipping would probably not allow you to buy from this source, but it is the best place I found to get the absolutely highest quality copper spheres...

http://www.necopperworks.com/copperballs.html

[Peterae]

Cheers tao just bought 2 of these  
http://www.amazon.co.uk/gp/product/B000X017W2/ref=ox_sc_act_title_1?ie=UTF8&m=A2JF9GMKKXF6FA

15cm Stainless Steel What a Bargain

[tao]

Brilliant

[Peterae]

  Just ordered 2 spools of 35SWG wire 1875m each and some 5mm copper track which i will try for my primary winding

[BEP]

You want to minimize corona discharge and maximize capacitive coupling to the air. The conductive surface of the globes should be as smooth and clean as possible, no sharp points.

Excellent point (no pun intended), ION.

We see many experiments with copper toilet tank floats and high expectations of performance - bad move  

Contrary to what many must believe, experiments in wireless power transmission must avoid coronal injection/discharge and the exciting lightning bolts.

Peterae,

Interesting comment about flipping the coils. As long as the coils are indeed planar that would be correct. If your coil will have stacked layers, even if it looks planar, the flipping may not have the same effect as a true planar coil being flipped.

The magnetic field of a planar coil is not simply 'compressed'. You should find that the high current winding must be on the same plane of the high voltage winding - NOT sandwiched with it. In effect, exactly as Tesla has shown.

--------

I have performed some of these experiments but somehow I drifted from illuminating distant light bulbs to blowing them out many years ago 

[BEP]

I just saw the posts about sources for metal spheres and scrambled to the websites  

When I must use these devices I turn them myself because either the cost is extreme or the seam cannot be made smooth enough. The costs are high (for the sizes I usually need) but the seams aren't very visible, if at all.

Do these folks blend the seams well?

Oh! Yes, the capacitance is between the two devices and is primarily the atmosphere. The two Earth connections are the two ends of the actual inductor to be tuned (the Earth). So, I think of the 'tuned' circuit as the tank made up of the capacitive atmosphere and the inductive Earth. These devices are just coupling circuits to that tank circuit. This is why the current meter is between the device and the Earth. A parallel tank is tuned by searching for a peak in current. The only parallel tank is the atmosphere and the Earth.

--- Only my opinion  

Before I run off for the weekend I wanted to clarify my reference to a planar coil as it pertains to basket-weaving.... I think the normal nomenclature for this type of Lorentz coil is called 'Spiderweb'.  A better description would be a woven pancake coil - all windings are on the same plane - all turns would only increase to coil's diameter.

[Peterae]

Hi WW
Yeah i could not believe the price of these spheres, i looked yesterday and could not turn up anything under £100 yet today first check and they came up 

I cannot see any seam although at first i was a bit worried about the bottom half looking dull, but i think this is just a reflection of something as i have now seen them else where and they are totally shiny all over, should be interesting connecting to them, i will try a self tapping screw.

Now for the basket weave former i am thinking of using wood for the spokes, anyone see any problems with this, and just leave the wire on the spokes and maybe varnish over the top to make it a bit more durable.

[BEP]

My favorite former is a CD disc segmented into pie shaped pieces. Rejoin them at the old cd center hole using a small bolt/nut and two large flat washers. Make sure the gap is even and equal between the pie shaped cd pieces.

After securing the coil with shellack or needlepoint remove the bolt, washers and cd pie sections.

If you need larger diameters just use your imagination.
   

[Peterae]

Yeah i had seen some use the CD as a former, i think this coil is going to be quiet large, i worked it out to be 66cm diameter for 35SWG wire even though it's only 0.2mm diameter theres going to be a lot of turns, i do need to try working this out again to be sure of the final diameter, the reason i ask about leaving the former in place is because 0.2mm wire will be easy to damage when trying to remove the former especially when it has been lacquered to make it more stout, if i get any sticking of the lacquer to the former it could break the wire, so i think it's a matter of working out whats best, PVC, wood or anything else anyone suggests, i have artists mount board which is 1.5mm or i also have pulp board which is a bit thicker, this would soak up the lacquer and support the whole structure to make it strong i think but then i wonder if there's any iron content, the mount board is made of cotton i believe.

Maybe wood is best.?

[BEP]

Wood always works well and it likes the lacquer.

[Peterae]

The way i understand a Spider web is to go top of spoke then behind spoke as each turn progresses leaving one width of wire between every turn, so looking at one side will show half the turns and looking at the reverse will show the other half of the turns, but of coarse each spoke has the full turns stacked, difficult to describe but this is what they did on one of the web sites to construct the spider web, so each spoke alternates front-back-front-back, and the when a whole turn is done the spoke count is odd so the next turn starts on the back-front-back-front etc.

Wood always works well and it likes the lacquer.

Thats great news, as i have just the stuff at my works 

[Peterae]

I have been trying to get my head around Tesla's use of opposite direction wound coils for the transmitter and receiver.

I can only think of one way they work, they need to be placed horizontally parallel to the earth, one clockwise and one anti clockwise, because if they were stood up vertically then when one is moved while walking around the room it would surely be possible when standing on one side to have both clockwise and if it's so important then they would stop working.

So if the purpose was to use them parallel to the earth then what happens when one is flipped over so they both are say clockwise, well if this stops them working, sounds exactly like the TPU

Although the patent seems to show them standing up vertically or is that just a good way of drawing them, it just does not seem logical to have them vertically unless they are aligned parallel to each other when one moves which does not sound practical.

[Peterae]

I think we can be pretty trust worthy of Tesla and his work there's also the chance that the Pierce arrow was merely receiving his transmitted radiant energy, which may lead me to believe that a TPU could merely be a replication of Tesla's radiant receiver, the transmitter could have been anywhere 

SM would have been laughing all the way to the bank, leave the transmitter on for a year or so and the receivers would continue to work 

[BEP]

I have a theory on the coil orientations. Of course, this makes little sense in standard radio communications.

Think of one as 'Spin-Up' and the other as 'Spin-Down'.

'IF' the completed circuit (xmtr & xcvr) is indeed a circuit the circuit is in series. If energy is to flow one must be opposite of the other. If the circuit was two batteries connecting pos - pos it would result in little or no current flow.

Regardless, whatever circuit it may be, a complete loop is needed.

There may be some propagation going on between coils. I would make both coils horizontal, to begin with.