HF HV Phenomena Observations

[Farmhand]

Voltage meter on the left, current on the right I need bigger caps on the power supply side too.

Input, Spark Gap And Output Observations And Documentation - YouTube

Right, 8:29am... Time for bed

Thank's for that dR, That will be a big help. I notice when the bulbs got bright
the gap was quiet, like fluttering as a soft flame would. An adjustable gap is
indispensable, next one I'll put a lot more care and thought into It's very important.

Cheers

[dR-Green]

Thank's for that dR, That will be a big help. I notice when the bulbs got bright
the gap was quiet, like fluttering as a soft flame would. An adjustable gap is
indispensable, next one I'll put a lot more care and thought into It's very important.

Cheers

Hi Farmhand, no problem Sorry I don't have time to reply to the rest you posted again, but I've been busy working on and thinking about this all night while watching one of Peter's lectures and skimming through a load of patents etc, and a thought just came to me which I don't want to forget. It might be easier to figure this out by making spiral coils and getting that to work properly, seeing as this is the system that Tesla developed and used before going on to make the MT version. I reckon it's pretty capable of interesting things without the extra coil if it's just a matter of scaling the size up a bit to get more length of wire, like the extra coil adds more wire

Also I was attempting some 1 wire AC motor things with one of the mini coils secondary connected to the spiral output, I didn't get the motor to run yet, but the streamers off the top of that coil were pretty intense, it even burned a hole through the aluminium apple pie tin I'm using as a (pretty useless) terminal. It can light the filament without any bucket connection almost as good as it does with it, I thought it was going to pop with the bucket attached

Anyway yes things are pretty quiet when the output is best, also that's when the input is lowest I think. If I make the gap smaller or bigger the output gets worse and the input goes up. I noticed last night though because I turned the fan off to record the sound, a lot of that whooshing whirring or whatever noise is coming from the transformer itself. I definitely think it's worth making a good spark gap though, as fine as you can make it, I'm not really happy with mine. But I took care since hearing the things from that Secrets Of Cold War Technology book to put the handle for adjusting the gap on the side that's coming from the HV transformer, I don't like the idea of being on the receiving end of the discharges coming through the gap

[Farmhand]

Also I was attempting some 1 wire AC motor things with one of the mini coils secondary connected to the spiral output, I didn't get the motor to run yet, but the streamers off the top of that coil were pretty intense, it even burned a hole through the aluminium apple pie tin I'm using as a (pretty useless) terminal. It can light the filament without any bucket connection almost as good as it does with it, I thought it was going to pop with the bucket attached

Yes I noticed the Plasma stream from my low voltage setup is like that, it can
burn holes in bulbs no problem, light paper and wood on fire, and if touched
with the finger tip it burns pretty bad. Hahah. I think that's a good sign.

Here's an old video with some small flame like effects, I ended up burning a
hole in the auto bulb I use towards the end, they get really nice yellow and
orange plasma in them. If the bulb is held still too long the heat burns through
the glass eventually. I even draw an arc with a pencil Don't know what I
was thinking with that.

Plasma 3.wmv - YouTube

Cheers

[dR-Green]

Yes I noticed the Plasma stream from my low voltage setup is like that, it can
burn holes in bulbs no problem, light paper and wood on fire, and if touched
with the finger tip it burns pretty bad. Hahah. I think that's a good sign.

Here's an old video with some small flame like effects, I ended up burning a
hole in the auto bulb I use towards the end, they get really nice yellow and
orange plasma in them. If the bulb is held still too long the heat burns through
the glass eventually. I even draw an arc with a pencil Don't know what I
was thinking with that.

Plasma 3.wmv - YouTube

Cheers

Hehe, very nice. I don't think I'll be touching mine any time soon I took the pie tin off to attach a loop of wire to the top of the coil to see what would happen, looked at the tin between the light and I could see loads of tiny holes in it. Pretty cool effects with the loop of wire though, when the arc breaks there's loads of flame like things going along the wire I think it would be pretty nice with uninsulated wire, not that the insulation will last long anyway but still, could be interesting. It tries to break out of the wire in all directions but the insulation stops it so it could be nice if it was all clean copper. Also the mini coil on the spiral output "receives" the energy better and produces better effects at the top with some capacitance or a filament bulb etc connected to the primary. Been playing around with some of the stuff in the one wire lighting patent. Very interesting, and the bulb is lighting a bit without even a capacitor or anything set up like it is with the transmitter and receiver. Except all the copper weights here are matched.

Ah I was going to try a pencil too, don't ask me why either

[Farmhand]

Have you tried connecting the primaries of both coils in series like the drawing
below ? Because mine are wound the same I connect the negative out of the
first one to the spark gap and the spark gap out to the other coil negative.
If the coils were wound opposite I could connect the positive of the second
primary to the spark gap, which would be better. The objective of doing it is
to make the coils opposite polarity for some experiments.



Uploaded with ImageShack.us

I'm going to concentrate on some other testing for a while. I've almost got
the first laminated iron ring core made to test out some ways to get 4 phases
from two. I'll make a post in the rotating field thread in the next day or two.
I'll wind four separate transformers on the ring. I hope to get a shaft and
bearings tomorrow. I plan to have several devices on the same shaft.

If I can see I can get four phases from two I'll go ahead and design a two phase PWM PCB.

Cheers

[Farmhand]

Hi all, I've been working on a power supply capable of a bit more juice, so I
connected a MOT to one of the secondaries of my newly wound converter, I
shunted the converter secondary with a pair of 2 uF caps to drive the MOT
primary and it seems to work well, I can get up to 110 watts into the system
at times but about 80 watts is good, I'm just going steady so I can spot any
potential problems so it's only short bursts for now, I'm still limited by the
PWM board having not thick enough traces.

This video is just a test of the converter and HV setup. The arc looked cool
so I thought I would share. At 50mm there is a rope like stream, there are
some arcs across 70mm, one discharge sphere is 20mm diameter the other is
17mm. I'm guessing there is at least 60 Kv there with no spheres I'm guessing
it gets to about 80 Kv. The primary cap is 19 nF. The converter is holding
about 200 volts across the MOT primary at about 1.3 Khz.

70 Watts Tesla coils.wmv - YouTube

With no discharge spheres to force an arc I can see there is an initial surge of
current of about 10 amps when I energize the circuit that quickly drops to
7 amps then slowly falls to about 5 amps when the terminals leak and the
current surges back and forth as the leakage is more and less. The terminal
voltage rises until it leaks, as it rises the current drops then when it leaks the
current is more to recharge the terminals.

The other output I connected a step down transformer to drive an ignition coil
from 15 or 30 volts depending on connections, that works well too.

I added an old computer fan to cool the PWM but it is almost worn out.
I'll have to get another one.

Cheers

Oh yeah, I think I'm going to need a sucker gap or a rotary gap to avoid the
heat, the spark gap tips are getting hot I think.

[Farmhand]

I want to try using some higher voltage to spark through my primaries so I
started to make some Leyden jars. It wasn't as difficult as I thought and it has a
maximum capacity of 1.3 nF which I think is ok. It should be good for fairly high
voltage. I have room for four of them on the plate, so that's about 5 nF.
Hopefully I can make them glow.



Uploaded with ImageShack.us

Cheers

[dR-Green]

Oh yeah, I think I'm going to need a sucker gap or a rotary gap to avoid the
heat, the spark gap tips are getting hot I think.

Hey Farmhand, that sounds interesting. I'll check out the video now. I've mostly been thinking about the spark gap for the last few days. I've cut grooves into the 6mm rods to make cooling fin type things to try and cool them down a bit, I haven't tested them yet but I don't think it will make much of a difference, maybe it will get me an extra couple of minutes before they get too hot again. So the next stage is to put a PC fan blowing into the spark gap to circulate the air a bit. And I'll put another fan to cool the transistors and rectifiers, also the power supply caps are getting a bit hot so I might just make a box and cool the lot down. The fans have been converted to run off a Bedini circuit, both fans in parallel get to a pretty high RPM and use less power than the original circuit.

I was thinking of going for 15-20mm copper rods for the next spark gap, but these cost £74-99. So alternatively I'll probably go for copper pipes to test first. These should be easier to cool, air can even be pumped through the tubes if necessary, and the ends of the terminals can be copper end caps or whatever they're called.



When these disintegrate they can also easily be removed and replaced with identical ones. Also the pipe itself can be cut and formed into its own heatsync etc. More versatile than solid copper rods I think.

[Farmhand]

Hey dR, happy new year.

I found this instructable about Tesla coils while getting leyden jar idea's, it uses
copper tubing and a T piece to make a sucker or blower gap, the spark gap is
between the ends of the tube, if they were very square it would give the same
dancing effect as flat tips but with much less expansion, even without a cap
and without as cap the air can blow right through the tubes.
I thought it was a good idea, using two spark gaps in series is another option
to decrease heat effects even further.

Pressurized spark gap

I found I need to start the setup with the gap a bit wide and let it expand to
tune in, which is no good. Rotary gap while probably the best is also the most
difficult to build and space hungry. So some type of static gap is the most
convenient I think.

I just realized the little step down transformer I have on one converter output is
only rated for 1.3 amps with parallel outputs at 15 volts , I've got a bigger
one that can put out 12.5 amps at 24 volts.

Oh yeah the two Tesla coils are opposite so there is only 35 Kv per terminal
but opposite.

Cheers

[Farmhand]

Some neat things about these jars is they are coffee jars I buy all the time, they
come with a plastic sealing lid by removing the glass part of the lid. The capacity
will be fairly uniform per jar and I can adjust the capacity by removing some
water, if I use a certain size dipper or large syringe to remove a certain amount
of water I can devise a system to adjust the capacity accurately to a quite high
tolerance. Still would need a lot of them for a big coil.

Cheers

P.S. I'll probably make another one tonight, if so I'll get some pictures and show how I did some things to make it easy and neatish.

..

[dR-Green]

[dR-Green]

Happy new year to you too

70 Watts Tesla coils.wmv - YouTube

Pretty nice spark What size coils are you using/do you have?

That pressurised thing looks good for ideas. What could also be done with the end caps is drill a hole in the middle, so it will be half tube and half flat electrode, so you could still get the air into the middle of the spark and have a decent flat surface area.

I found I need to start the setup with the gap a bit wide and let it expand to
tune in, which is no good.

How do you mean?

The syringe thing sounds like a good idea. This seems to be another good way of making bigger caps along a similar method, basically using many Leyden jars in parallel inside a bigger bucket

Bucket Caps With Billy and Chris - YouTube

Anyway I was showing a friend some stuff the other day and I ended up doing the aluminium tape attraction test with paper

Incandescent Bulb Attracting Paper - YouTube

And then holding a bulb between us. The coil output was connected to the pipe in a bucket of soil and I was holding on to the other copper pipe with one hand and one terminal of the bulb in the other, my friend on the other side of the bulb acting as a capacitance, or whatever.

A Bulb In Hand(s) - YouTube

Also while doing that happy new year image with the fluoros I forgot the wire was connected directly to the coil and consequently discovered that the output is safe to handle when I'm on the other side of the filament bulb, as long as I don't let go and make it spark into my finger.

[Farmhand]

Oh I see you done the sign yourself with your setup. Cool.

I just meant that if I start the setup with the gap a bit wide as it heats up and
gets smaller it becomes closer to right gap width.

I'm using the small coils I made, I changed the secondaries to some other ones I
had which have the same wire length as the "B' coils, the tension at the
terminals is a bit more with a bit less input.

I'm still experimenting with the supply circuit, I need a bit more voltage and
power so I'll try a few things over the next few weeks. We had a violent
storm a few days ago and some trees were downed on the fence so I have a
bit of work to do before I can spare a lot of time. My billy goat has turned
into the demon from hell because he is in rutt, so I have to be careful he
doesn't turn me into a human frisbee. But if I don't fix the fence he'll
chase the females into the ground. Wish me luck, I could end up a horn
ornament.

Cheers

[Jiffycoil]

Nice work everyone. There are so many types of discharges that you will see from different types of coils.

Here are a few:

Bi polar conical coil:


Plasma by jiffycoil, on Flickr

Pancake coil:


pancake coil by jiffycoil, on Flickr

As compared to a traditional Tesla coil:


My first Tesla coil revised by jiffycoil, on Flickr

Bands of plasma tracking across a spherical top load.


Plasma Bands by jiffycoil, on Flickr

I like the discharges from smaller lower power coils the best. I need to setup the pancake coils and take some more pictures. Their output is amazing.

[Farmhand]

Nice photos jiffy, the different types of discharge are very interesting. Thanks
for sharing those, I was hoping people would post more piccies.

As I was experimenting tonight I noticed a curious effect where there appears
to be a higher voltage present on an unpowered (by wire's) coils terminal than
there is on an identical one right next to it which is powered.

Here's the arrangement.


Uploaded with ImageShack.us

And a video showing some of the effect making itself known.
Effects 88.wmv - YouTube

I can think of a reason or two why I think it might be happening.
But I would be interested to hear from someone else some possible reasons.

It appears there might be two antinodes (hv) one at the top of the secondary
where the sparks are breaking out to the primary and one at the end of the
coil "B" at the terminal.

I think the sparks would still be going from the secondary to the primary regardless of the coil former type.

Cheers