Donald Smith Devices too good to be true

[tswift]

Another option for large tubes in 8" and 10" sizes is cardboard construction tubes. These are used as concrete forms for pouring posts and are sold in hardware and home improvement type stores. Note that the sizes are NOMINAL sizes, they ship a slightly-smaller-than-8", a true 8", and a slightly-larger-than-8" all telescoped together. Take a measuring tape when you grab one out of the bin so you get the size you're expecting. Cost: about $5 for a 4-foot tube.

Unfortunately this is a somewhat inferior option to PVC. The PVC is stronger and more rigid and won't deteriorate or absorb moisture like the cardboard can. But will it work? Yes, I have my little tabletop slayer exciter/Tesla coil wrapped around a cardboard mailing tube and it works fine.

[soundiceuk]

Another option for large tubes in 8" and 10" sizes is cardboard construction tubes. These are used as concrete forms for pouring posts and are sold in hardware and home improvement type stores. Note that the sizes are NOMINAL sizes, they ship a slightly-smaller-than-8", a true 8", and a slightly-larger-than-8" all telescoped together. Take a measuring tape when you grab one out of the bin so you get the size you're expecting. Cost: about $5 for a 4-foot tube.

Unfortunately this is a somewhat inferior option to PVC. The PVC is stronger and more rigid and won't deteriorate or absorb moisture like the cardboard can. But will it work? Yes, I have my little tabletop slayer exciter/Tesla coil wrapped around a cardboard mailing tube and it works fine.

You could always get some vehicle spray paint and lacquer. Then you could have any colour you wanted. It would be water proof too!

[soundiceuk]

Driver i used is based on 4046/4049 chips. Changed resistors (potentiometer) and capacitors for tuning.

Red led will light up when in resonance. at the moment with this flyback 75khz (max 35kvdc) input 19v AC half-wave rectified to DC. PVM pcb will be made today.

Different types of flybacks.
(1) from color TV 8kVpp
(2) and (3) from b&w TV 15-20kVpp
(4) diode split transformer 25kV DC
(5) flyback with integrated cascade 25kV DC

Which flyback are you going to use with home made PVM12 ?

[soundiceuk]

another technical request


How much level can the earth ground quality effect an over energy device ? i am doing some experiment where the earth play a critical role , standing waves can be seeing very easily either with a small light bulb or using a scope probes ..

all the test are based on the ETBC but with a ferrite rod inside, the capacitors banks can be charged only when there's an earth ground, now the question arise to how much level will affect the system ?


thanks in advance !

The earth ground is definitely important. Hence why Tesla used a 300ft deep earth over an aquifer for Wardenclyffe.

Yes, this is very exotic and unachievable by 99.9999999% of people.

You just have to do your best, based on your funds.

An 8ft deep dedicated ground rod is most probably going to be a basic necessity.

[tswift]

Kilovolt meter

One of the challenges I have had troubleshooting is the lack of any good way to measure high voltages. I made myself a kilovolt meter from a high value resistor and an ammeter. By Ohm's law, current equals voltage divided by resistance. Since we want to put the minimum possible load on the circuit, we want the highest value resistance obtainable and the most sensitive ammeter. I found a 0-100 microamp analog meter (scale reads 0-10 but meter reads 0-100 uA) from ebay, and I obtained two 20KV rated resistors to go with it, a 100M and a 1000M. Doing the arithmetic, connecting the meter to an HV source through the 100M resistor will give 100 uA of current (full scale) at 10KV voltage. If I use the 1G resistor the range is 100KV full scale, with the caveat that the resistor is only rated for 20KV and might have problems at voltages much higher than that.

I have attached a picture of this arrangement being used to read the voltage across C1 with the PVM12 running. Using the UX-FOB diode I only obtain a little over 2KV (this is with the 100M resistor. I also tried the HVM12 low-speed diodes and my new 30KV high-speed diodes and to my surprise it made no difference! I changed out the C1 capacitor for a new one with the same specs (this one came from ebay), likewise no difference. So I am left with the conclusion that my PVM12 is probably bad. It turns on and runs but it should be charging much more than this. Thankfully, as a backup I have obtained one of the ZVS/flyback combos previously mentioned in this thread. This is considerably more powerful than the PVM12, but just charging a cap shouldn't require any real output power. Sure enough, using the ZVS to energize the circuit and using the flyback internal diode like Mwtj did, I measure around 12KV on the cap (using the 1G resistor) and the whole circuit is crackling with static! Numerous surfaces are charged to HV potential, such as the whole L1 coil. It is becoming obvious why it really is a better idea to use HV-rated insulated wire for this circuit, it's only going to get worse at higher voltages.

[tswift]

For those who are browsing but aren't members of the forum, here are the same images hosted on an external server:

[Mwtj]

Take your pick?

Which flyback are you going to use with home made PVM12 ?

I did try the whole box today. Got some flybacks that only put out AC.

Will be using the gray flyback with 360kv multiplier.

[Wistiti]

Will be using the gray flyback with 360kv multiplier.

360kvdc!!! Will you have to change your 30kvdc wire on L1??

[soundiceuk]

I did try the whole box today. Got some flybacks that only put out AC.

Will be using the gray flyback with 360kv multiplier.

That's a big box! Are they all yours?

What made you pick that one?

360KV multipler!

What are your antenna ceramic insulators rated to?

Are you going to do this with existing circuit or have you built the mirror circuit?

Was just thinking how your tuning cap would cope with 360KV.

Have you had that multiplier running yet?

[Mwtj]

360kvdc!!! Will you have to change your 30kvdc wire on L1??

Well we have see how that works out. Do not know how everything will react in this circuit. But soon we will see.

[soundiceuk]

360kvdc!!! Will you have to change your 30kvdc wire on L1??

Calculate the voltage between turns.

Mwtj did you get 40KV or 30KV wire?

[Mwtj]

Wire is 30kv. Multiplier did work that i build with the flyback. Voltage is adjustable.

I need too wait on the 360kv multiplier and the caps that go with it. Could take weeks.

For the moment the single circuit will be used.

[Wistiti]

I think I have found a really great bargin for the hv wire....
Will let you know soon...

Here is the best deal i have found on 40kvdc wire...
The price is $/METER!!!
https://addison-electronique.com/fil...t-voltage.html

So if you buy 300meters and more it is 0,17$/meter

[Wistiti]

Another option for large tubes in 8" and 10" sizes is cardboard construction tubes. These are used as concrete forms for pouring posts and are sold in hardware and home improvement type stores. Note that the sizes are NOMINAL sizes, they ship a slightly-smaller-than-8", a true 8", and a slightly-larger-than-8" all telescoped together. Take a measuring tape when you grab one out of the bin so you get the size you're expecting. Cost: about $5 for a 4-foot tube.

Unfortunately this is a somewhat inferior option to PVC. The PVC is stronger and more rigid and won't deteriorate or absorb moisture like the cardboard can. But will it work? Yes, I have my little tabletop slayer exciter/Tesla coil wrapped around a cardboard mailing tube and it works fine.

Good low cost idea!!!

[Wistiti]

Steel and aluminum bolts for the PPV .