Donald Smith Devices too good to be true

[tesluh]

Can anyone identify the diodes in this video (or on dons board) ? He says they are HVD35-10 diodes in the video description but I have no way of knowing, cant find those listed for sale. The ones I'm using don't seem to be working correctly and want to find some that another person has used with success.
[VIDEO]https://www.youtube.com/watch?v=43hted5YTCw[/VIDEO]

[soundiceuk]

More progress

[tswift]

If you want to see the full resolution 10MP versions of all these photos instead of the scaled-down ones, you can use the master IPFS link at:

http://gateway.ipfs.io/ipns/QmeamoEj...hxNgB5wFiwYPtz

This will take you to a directory folder listing which has all the pictures. The file names correspond to the ones in my posts on the forum, only without the "_small" suffix. Be aware that it can take QUITE a while to load the folder listing the first time, as in several minutes. It's also very slow for a few hours after I post new photos, at least for the new files. As near as I can tell from testing, it always works eventually but you may have to give it a while. Because this folder link uses IPNS (which is part of the IPFS specification), it will always be the same even when new files are published. The actual IPFS folder hash changes every time, which is why they created IPNS....

[tswift]

And finally, a trial layout of the whole rig to see how it's all going to fit together. It's going to be smaller than I thought at first: I can put the secondary tuning cap on top of the resonant coil assembly and keep the wires shorter and layout more compact. Now I need to acquire a few miscellaneous hardware components for assembling and begin actually putting it together.

I hope some of you are finding this all this documentation valuable: it takes longer to write up explanations and edit photos than it actually does to experiment. I know we have some folks here who are capable builders with lots of experience and probably don't need my explanations, but I want to have a practical step-by-step that's easy to follow for everyone else who doesn't have as much experience. If we arrive at a replicable working design then we can produce an explicit set of plans and instructions, or perhaps some brave soul will make kits available. However, even in the absence of a kit or plans, with just a little engineering one can work with whatever parts you can find/afford.

[tswift]

All right, after calculating the step-down ratio, it's easy enough to put it to the test with the function generator. The function generator is driving the L1 coil at resonance (tuned for approximately 500 KHz), through a 10K resistor, with the oscilloscope measuring the voltage across both L1 and L2. The measured voltage across L1 was 15.0V peak-to-peak and the measured voltage across L2 was 0.816V p-p. This gives a measured step-down ratio of about 18, versus 16 by computation. Still definitely in the ballpark.

Note that for this test the cap across L2 is not used. It's strictly operating as an air-core transformer.

[tswift]

Well, it looks like everyone is making progress, very encouraging! Here is some of my latest activity. I have started adjusting the layout on the bench to resemble the final desired assembled result. I also took some measurements to find the output voltage from the secondary. It needs to more somewhat more than 12 volts but not hugely more than 12 volts. The voltage step-down ratio of the resonant transformer stage will be determined by the ratio of turns of course, but it's more complicated than this because (1) the flux coupling coefficient between the primary and secondary is not close to 1 and (2) the primary and secondary are quite different in size and have quite different inductance. There are formulas for all this of course, taken from standard electrical engineering and used commonly in Tesla coil design and ham radio practice:

V2 = V1*k*sqrt(L2/L1)

Where V1 is the input voltage to the primary, V2 is the output voltage from the secondary, k is the coefficient of coupling, and L1 and L2 are the respective coil inductances measured separately.

It's easy enough to put an LC meter on the coils to measure inductance, but how do you measure k? There are multiple ways, but one of the easiest is to measure the primary by itself, and then again with the secondary shorted. The measured inductance will be less and with a little algebra you can find k from these measurements. The formula is:

Lsc1 = (1-k^2)*L1

Where Lsc1 is the measured inductance of L1 with L2 short-circuited. So I did this and found:

L1 = 977 uH
Lsc1 = 857 uH

which gives k of about 0.35. It works equally well measuring the secondary while shorting the primary:

L2 = 29 uH
Lsc2 = 24.2 uH

and if you work the math it gives a fairly similar result, within experimental error. So as a whole this assembly should be expected to give a voltage ratio (going back to the first formula above) of about 0.06 ( k*sqrt(L2/L1) ), or a step-down ratio of around 16:1. If the breakdown voltage of the spark gap is set to something like 1500 volts, then the voltage at L2 should be something under 100 volts. This might be good enough, or I might have to reduce the turns on L2. At least to begin experimenting it's probably good enough.

A good resource on mutual inductance and coil coupling:
Coupling Between Coils

[soundiceuk]

"Partial completed hv side

Waiting for stuff to complete the spark gap.

60kv capacitor total 1nf
10mOhm 25kv resistor
100pf 11kv aircapacitor
Glass vacuum capacitor 50pf 10kv if needed
Green cap 30kv 470pf
Two 20kv 100ma diodes.
Zvs driver with old style flyback 30khz
Black thick wire is going to antenna."


Great job! ZVS is very efficient!

[Gedfire]

Do, NO TRY.

Gedfire I thought you was talking about Lasersabers atmo motor.

Just watched the link...

See what tswift and the others conjure up and then decide what is more advanced.

I tell you this, the neon sign dimmer is in SERIES resonance to the rest of the circuit.Its all self resonance via the dimmer circuit.I tried the dimmer switch capacitor to car coil device.That's when i dawned on me that it was series resonance going on here.
Don had it on on most of his devices.

@Soundiceuk.The fun begins on page 23 of Bruce's Doc .See attached.If Don's Doc you mean, let me know.I have posted them before.

What I need now is a large metglas core....

[DigitalM]

Thanks a lot for HD fotos and your research.
However, I do not agree with coil devision. You can see 24(+-1) turns of antena coil.
So, we have 24+40 turns. Its 8 turns for 1/4 wave
L1 is part NO 3033 and 5 turns of L1 have same lenght as 8 turns of L2.

[qwekw]

1K Ohm AMPHENOL Multi-Turn Trimmer 992P

(CTM) 304 - 115 - 550 pF, 500v


Inductance uH:_67.0

Coil Length:___4

Coil Dia:______1-3/4

Turns per Inch:16

Wire Size:_____18

some data abouth smith coil

lc coil is 3/4
antena coil is 1/4

[DigitalM]

L2: 2" coils 25+50 turns of AWG 18
CAP L304: 115-550pF 250-500V
RES: AMPHENOL ???

[soundiceuk]

It will be interesting to see how much different elevations around the world differ with your replications.

Anyone live near the northern lights?

[Mwtj]

Great! Get right on it.

Tube is al little bigger than 6 inches ( 16cm).

Unfortunaly i am only about a 300 feet above sea level. A little less than i thought

[soundiceuk]

Setup for testing.

Copper wire is on its way. Yellow tube is going outside to the antenna. There are two ground connections behind the coil.

You can use HV wire for a lead in from the antenna.

What tube is it?

[Gedfire]

What Lasersaber has done is great!

However it has moving parts and is inferior.

The only moving part in Bruce's design is the plasma spark that jumps the gap!

It is also the only noise too. A quiet hiss.

Bruce's machine? He could just use XRAYS.He knows this.Higher frequency striking metal.He had the patent in his Draft Document with his ion valve.He also knows the plasma will generate XRAYS UV and even gamma rays under certain circumstances.I know this because I have two Radiation detectors and plasma from my spark gap AND corona discharge cermaic ozonator produces copius amounts of XRAYs.