Donald Smith Devices too good to be true

[Duncan]

Thanks Duncan.
f=w/2pi


So to know the exact capacitor one have to know inductance and frequency yes?

Whilst I'M not hyping this company in particular ,, I would seriously think of working along the same lines lines (or some thing similar) / Its relatively cheap and its the foundation of Mr Cleans circuit . ( which you’ve seen working) As you will see It has the advantage of a variable frequency HT power supply this company sticks you £50 for the unit but the schematics there and a 555 will cost buttons .. with a variable frequency supply you can tune anything to anything (within reason) couple of coils from the scrap yard .. It makes sense XL is directly proportional to frequency and XC is indirectly proportional to frequency so get some where near and then hit the nail right on the head by altering the frequency slightly.. takes a lot of the hassle away
RMCybernetics - DIY Mini Tesla Coil

[boguslaw]

Here you see something interesting :
Качер2.MP4 - YouTube

Another miconception broken ; we can charge low voltage capacitor from HV output.
If rate of charge would be too fast then a protection device is useful for example varactor or transil or varistor....

[Jacqui]

unless you have a nice variable HT supply like Mr Clean .. yes
but normally get very close and then alter the coil connection slightly XL is the way to go.

Hi Duncan , I'm new here , so hello to everyone . I'm curious Duncan , as to why altering XL is a better way than altering a variable HT supply ?
Jacqui .

[Jacqui]

Whilst I'M not hyping this company in particular ,, I would seriously think of working along the same lines lines (or some thing similar) / Its relatively cheap and its the foundation of Mr Cleans circuit . ( which you’ve seen working) As you will see It has the advantage of a variable frequency HT power supply this company sticks you £50 for the unit but the schematics there and a 555 will cost buttons .. with a variable frequency supply you can tune anything to anything (within reason) couple of coils from the scrap yard .. It makes sense XL is directly proportional to frequency and XC is indirectly proportional to frequency so get some where near and then hit the nail right on the head by altering the frequency slightly.. takes a lot of the hassle away
RMCybernetics - DIY Mini Tesla Coil

Oops it seems this answers my question .

Jacqui

[Duncan]

It isn't I get the impression that he doesn't have a variable frequency PSU ... which of course makes everything very much easier .. Ive just been trying to do it with NST and a frequency going all over the place Its going to get drop kicked!

[mr.clean]

wow

I was simply pointing out what the mechanism is that sets the secondaries in motion. The event in my test was simply an extreme example of what is going on, smaller devices obviously would operate on a much smaller pulse.

Dumping a .005uf cap at 5000 volts into a coil of say 50uh would give you a pulse of around 50 amps depending on the coil and it's internal resistance as well as the capacitors characteristics.

With a loose coupling a reasonable portion of the amperage would be transferred to the secondary coil(s). We want to contain the primary event in the secondary oscillator and allow the secondary to "freewheel" at it's natural resonant frequency. This is where tesla states that an "activity" in excess of the input is created. Not overunity - an activity...

The primary tank, if constructed and tuned precisely, will require only the initial input and enough to cover any losses that are inherent to the system then it simply recycles the amperage. This activity is transferred to the resonant secondary which operates in a similar fashion.

The problem arises when power is to be extracted as any load you place on this "freewheeling" activity will alter the parameters of the circuit. An example would be to measure a standard transformers inductance with no load then measure the same with a resistive load on the secondary... the inductance is changed considerably which means you have to back to the beginning and retune the entire system to that particular load. This makes the resonant system quite proprietary to it's output.

In order to make it less dependent on a load you need to separate the input and output. This is typically where the problems arise and you start playing the "time" game - that is charging caps at HF and discharging small amounts at a lower frequency. Tesla also stated you can only remove that amount of it's natural accumulation. Keep in mind the cap/inductor discharge also applies to output circuits as well.

If you look at Don's original drawings, he was depending on the primary tank circuit as the only resonant portion of that circuit, the output coils were simply set up as a full wave rectified output to charge capacitors then to be discharged through an output transformer via inverter circuit, most likely a distribution transformer. This tank circuit had to be precisely tuned to the charging load presented by it's secondary system.

GREAT info man!! THOSE are interesting points!!

[soundiceuk]

If you need help with building Tesla coils i can recomend the guys at www.telsauniverse.com chat room. They live and breath 'Coiling'. Just don't mention ou devices at all. They are so helpful as long as you don't try and educate them on ou. They get really funny with you if you do.

Hey Mr Clean, why don't you measure your amperage output by blowing car fuses?

[Farmhand]

Dealing with the output is definitely a challenge... I put together a rotary spark gap inverter to discharge the storage caps through a distribution transformer. My tests with this so far has proved to be one possible solution. Below a schematic of a basic spark gap inverter and the rotary device I built for testing the idea... I used a MOT in reverse which isn't the best choice as I'm limited to input voltage but it proved this would function as expected. I'd like to build a commutator make and break with some adjust-ability in the pulse width.

Considering the action that takes place in the cap/inductor discharge where you loose 90% of the voltage to convert to amperage you can come fairly close to calculating the output side to get a more useable voltage without all the conversions. As an example, say we have a 10 turn primary that we dump 5000 volts into and 90% is converted to amperage leaving 10% of the voltage intact or around 500 volts. Divided by 10 turns we have 50 volts on each turn which is transferred to the secondary coil. We need, say, 250 volts for our output inverter so our secondary would be at or around 5 turns. Most likely slightly higher factoring in the loose coupling. Basically, we need maintain as much amperage as possible cycling in the primary tank, tuned to reduce input requirements as much as physically possible, so the transfer to the secondary maintains a reasonably high amperage with the voltage level needed in our output. Inductive heating circuits are good ones to follow for the primary tank. Tesla mentioned briefly that when he placed a foil in close proximity of his primary coil it would disintegrate instantly giving us a good idea of the currents circulating.

I'm playing with a few ideas that should show this whole process can be done at a much lower voltage. Remember, we aren't building the classic tesla coil here.

Awesome, I was thinking a rotary switch or spark gap would be the best way,
maybe you could put 4000 volts through two MOT's in series. Though building
the transformer to specs would be better, two MOT's are cheap if they are
reclaimed.

In my opinion I won't be bothered to build the resonant part of the circuit
unless I can convert the output to 60 Hz AC at about 240 volts. The output
down conversion can be applied to any HV source that can charge the caps in
order to test it's function.

Good stuff Dragon.

Cheers

[Farmhand]

Well after my little interaction with Dragon, it was time to hunt down some
transformers while I was at the recycle section of my local rubbish tip getting
transformers I also found inside a huge microwave oven the fan was being
used to turn the cooking plate through a reduction gearbox via a belt, this
might be able to be modified to a switch/commutator, the motor is heavy duty
for a MOF motor and looks as if it might have real ball bearings. The reduction
is too much to be useful for a 60 Hz switch but maybe I can rig something up.

I got four transformers the big one center left has a 220 volt tap on the 240
volt primary and the secondary is huge the wire is about 0.5mm in the
secondary. And the secondary looks to be about twice as big as the smaller
ones have.

I needed two similar ones to replace the two I think I damaged by using them
to power a spark gap when their cores were not grounded, at least now I can
test if they are damaged or not by trying the new ones, they were in the
weather so I will leave them in the sun to dry for a couple of days before I try
to use them.

There must have been about 40 other HV transformers available there like
flybacks and stuff also different types of motors and stuff, flybacks look much
more difficult to retrieve though I might go back later in the week.

I insisted they take at least $5.00 for the transformers. Bargain.



Uploaded with ImageShack.us

Cheers

[mr.clean]

cool experiment, and thanks for the TC site

If you need help with building Tesla coils i can recomend the guys at www.telsauniverse.com chat room. They live and breath 'Coiling'. Just don't mention ou devices at all. They are so helpful as long as you don't try and educate them on ou. They get really funny with you if you do.

Hey Mr Clean, why don't you measure your amperage output by blowing car fuses?

like charge up caps and detonate them thru some fuses? cool!
ok i'll do that right now

[dragon]

Those scrap yards make me feel like a kid in a toy store ! Great find. The biggest problem I've found with the MOT's is they need a voltage much higher than they can handle to bring the output up to a useable level. Good for testing but I don't believe they would handle a final design. A nice small 15kv pole pig would definitely fit the bill or something custom made and oil filled.

There are some interesting video's on youtube showing how the distribution transformers are made. Wouldn't take much to make up smaller units for our purpose.

I fully agree that the output is almost more important than the input circuit. Charging the caps is a fairly easy task, dealing with the HV output is considerably more challenging.

[dragon]

like charge up caps and detonate them thru some fuses? cool!
ok i'll do that right now

Wear some safety glasses with that experiment... also look into EMP devices or exploding wire EMP devices to see how much energy is disapated in such a discharge.

Here is a good place to learn about some of these... Wire Exploder / Blast Art

A good book to learn about some of this stuff is called "Electronic gadgets for the evil genius" - from tesla coils to EMP weapons - never a dull day...

[mr.clean]

Those scrap yards make me feel like a kid in a toy store ! Great find. The biggest problem I've found with the MOT's is they need a voltage much higher than they can handle to bring the output up to a useable level. Good for testing but I don't believe they would handle a final design. A nice small 15kv pole pig would definitely fit the bill or something custom made and oil filled.

There are some interesting video's on youtube showing how the distribution transformers are made. Wouldn't take much to make up smaller units for our purpose.

I fully agree that the output is almost more important than the input circuit. Charging the caps is a fairly easy task, dealing with the HV output is considerably more challenging.

YES, definitely the problem,

Hey, question.. i want to use a relay and this other square gen i made for cap pulsing at 60hz to output,

(i know about the resistor/lowing freq and volt divider arrangement)

But i want to try it this way, to keep the caps charged rather than dumping all at once everytime.

Ive been looking around, but no one is using 600+ volt caps and a relay w/signal gen,

how to keep these charged and pulse at 60hz?? any advice?

[FRC]

Transformers

Farmhand's transformers look similar to halide light transformers. Can 1000 watt
halide light transformers be used as an HV source for experiments going on
here ? I think someone mentioned something about them here on a previous post.


George

[kenssurplus]

Hi All,

For the output matching to 60 hz this is my solution:

FWBR -> high voltage dc storage caps -> rotary variable capacitor -> modulates output step down transformer at 60 hz.

No transistors / or other high smoke content components