Gray Tube Replication

[Aaron]

bridge

Geotron,

I've fried a few mots myself.

What kind of bridge do you have leaving it?

When I had just a 1kv bridge made from four 6a100's,
I had problems even when I had the output like
500v or so.

But suddenly when I used eight 6a100's for a 2kv
bridge, the mot worked flawlessly.

[Guest]

Hmm... I had just attached a single 3A 1000V diode to the AC output,
then connected right on to the CDI caps without a resistor, as it had
been limited to 1.3A or so at 220V. The LV charger side with the 6V
wall-plug transformer was setup in the same way.

I'm glad to know it was just not enough diodes to block whatever
was attacking the coils... although with my lack of an immediate
replacement transformer I may try pulsing 12V directly though a
CW multiplier just to see how it goes. I'll definitely be loading
up the output with blocking diodes too - the punch of this thing
is amazing...

[Aaron]

mot full bridge for hv side

Hmm... I had just attached a single 3A 1000V diode to the AC output,
then connected right on to the CDI caps without a resistor, as it had
been limited to 1.3A or so at 220V. The LV charger side with the 6V
wall-plug transformer was setup in the same way.

I'm glad to know it was just not enough diodes to block whatever
was attacking the coils... although with my lack of an immediate
replacement transformer I may try pulsing 12V directly though a
CW multiplier just to see how it goes. I'll definitely be loading
up the output with blocking diodes too - the punch of this thing
is amazing...

For you, it possibly might be the same issue. I just know that for me
using a full bridge from the high voltage side made of 8 x 6a 1000v
diodes did the trick. I hope it is that simple for you. I'd definitely use
a full bridge in either case.

[Guest]

The way it was showing up before, the transistors would heat up on one
coil while staying cool on another, while currently they are all now
generating nothing other than resistance leaving the coil to pick up
only a minor voltage. Metering shows the transformers to register on
the Ohms scale as they should; in any case this is the layout



also, the diode bridge was not being used

[Guest]

After a bit of changing things around it seems to be working now without frying anything up,
except one transistor out of my LV charger that is more than likely stuck open. I've added
3KV worth of diodes to the (-)output of the transistor and timer circuits in order to help
block anything from going backwards into them, as well as 3A fullwave rectifiers on the
transformer outputs.



Curiously at last measurement there was around 530V 3A DC being produced on
the LV side transformer from the bank of 5 transistors out of the 250W 12V power
supply, measured without a load. At this point it has returned about one burst
per second with 1/4 - 5/8ths gaps on the rods from three 250V 22uf capacitors.

I'll be reworking the transistor wiring to equally distribute flow between them,
but as for increasing the rate of discharges, my best ideas are to decrease the
spark gaps and use a thicker transformer.



HV plasma - top LV caps - left

[Guest]

I've taped a small demonstration video of my 2000ft spool of 25g wire bouncing
a couple of small neo magnets. The Lv side was being fed with about 500V from
a bank of five transistors pulsing 12V from a battery through a 100w transformer.

Much better results now with using a 12V motorcycle battery in place of
the 250w PC power supply - many more bursts per second, even though it is
a bit out of service from sitting too long and will not run an engine. Its
negative pole is connected to the output and also directly to ground, looking
like it may work even better instead with a gap onto ground, perhaps sealed
in a box.

The scr diode was not seeming to work with about 1.5V reaching its gate,
instead turning into negative voltage upon being connected by an interruptor.
It may be the datasheet is wrong... it shows a notch in the gate lead, and
the ones they sent me don't have any notches.

With a raised frequency at 50% duty cycle it has upped the LV side output
to over 700V. The way in which the percentage can be varied has me intrigued,
shown at Electronics in Meccano. The LV side capacitor voltage seems to
float around 150-200V when in operation at slow speed; 4-6 contacts per second.

Using a rewound center tapped transformer will be my eventual direction if PWM
and additional transistors are not sufficient. Thanks for your patience
in helping me along Aaron and others with this truly incredible energy...

With a leyden jar it seems to fan out from the anode and light up the wire
on its way through the copper lead connected to ground -

[Guest]

It has gone awry and done away with my ignition coil... I'm seeing that
with the 3rd point output connected directly to the (-)battery with a
short gap to ground that the entire discharge is being absorbed into it
rather than sparking across.

Amidst an experiment to see whether a PC fan connected to a separate 12v
battery may operate normally with the discharge output connected to the
(+) pole instead, some event took place that fused the coil together.

Anyway, initially the Run battery showed to be recovering energy from having
its (-) pole connected to ground, into which the radiant bursts were traveling,
then with the output going straight into it instead it was steadily losing
voltage.

Does it seem right that the output may be directed into the (+) pole
of a battery simultaniously powering timers and other delicate circuitry,
acting to condense it into useable charge while sustaining a proper
voltage to the electronic components?

[Guest]

charging up!

edit: The triac, as I've learned is being used in light dimmer knobs around the
world, and being a short-signal component will likely not provide the desired effect
of ac-transformation.

I'm seeing now that the way to go is with an inverter coupled with
voltage control for driving the LV side power supply transformer rather
than pulsed DC...

Aaron, you've clearly shown this in practice utilizing a variable
transformer to charge those caps, and it got me wondering if another
proper way of going about it might be with a household light-dimmer
knob. I'm sure that I would like to use a variac, only with the
relatively high cost of obtaining one it has sent me to look for
alternatives. Another possibility I'm considering is a power tool
speed control box, as is commonly produced for routers.

[Guest]

info

The high voltage generated from the output of the ignition coil does
not seem to want to transform into plasma with the use of 1000V 1A diodes
in series. The previous blocking diode that broke on my ignition coil
was rated at 10mA, so it seems a nF capacitor would be in order next time
with such a rating.

The video previously shown in which a transformer was sparking backwards
a surprising amount is what I have learned can be due to either a faulty or
absent diode for the generation of a plasma burst. The LV capacitors
will not collide properly in the spark gap; rather on the coil sending
the HV burst from shorting a capacitor... also causing defective transistors.

[pranav2010]

my test video

hi arron

i just test my circuit

circuit works very well

i solved a problem of power resister heating

but one new problem i am facing when i increase voltage amp goes very high it goes up to 19 amp i dont understand why it happened

i think it happened because of the bridge of MOT

i just purchase 16 amp 1200v diode

i am going to use it like to you

and one more think is when i connect lv to hv diode circuit doesn't
trigger

please check this video

YouTube - SNC00364


have wonderful day

[Aaron]

Gray Tube Replication

You guys have been busy.

Pranav - it looks like you definitely got it!

Can you post a diagram?

Geotron - I'll have to look at all your posts soon, just been busy.

[pranav2010]

circuit diagram

hi arron

i attached circuit diagram please check it

i made bridge with the 1x3 microwave diode i think this is the problem in my circuit

and one more think is while applying dotted diode circuit doesnt trigger

i dont understand why this happened

have wonderful day

[Aaron]

Hi Pranav,

Looks nice and simple, thanks!

With 22uf on the front side, that is probably enough
that you don't need the diode (dotted line position).

You show you have an isolation transformer on the
front but I had problems even when using an isolation
transformer.

You could run one of the transformers from an inverter
connected to a battery.

Anyway, if it works without the dotted diode then
I wouldn't worry about it. I have done it with or without.

You mention the bridge with 1x3 diodes. Do you mean
you have 12 diodes for the full bridge? What are their
specs and what is the max voltage you are outputting
from the MOT when you turn up the variac?

[pranav2010]

diode

hi arron

1x3 is the number of microwave diode its rating is 12kv 500mamp

i am giving up to 1700v to cap

its charging very well

all circuit working good

i think diode is the main issue in my circuit

what do you think

after success of this i am using my circuit which i developed

i will definitely tell you about it

let me do this first

this success is all because of you

have wonderful day

[Aaron]

@Pranav

Hi Pranav,

Thank you but it was definitely your persistence that paid off!

Below, I removed the diodes between bridge and cap. Are those
necessary? Were those also high voltage diodes? You can leave
them of course if it works fine.

Are the 20x diodes MIC 6A4? So 400volts 6amps?

Also, your full wave bridge - what part number are those diodes?
And does the bridge use only 4 diodes total?