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I picked up an old 14" monitor at Goodwill for $2.00. It worked. I
removed the flyback transformer for HV experimentation.

I hooked up a 9 volt battery on the input and setup a small gap
between the HV output and hv return. I though a momentary 9v pulse
would produce an observeable spark on the output. No such luck.

Any suggests?

Bob

--- In Electronics_101@..., "rsnyder187" <rsnyder187@y...>
wrote:

I picked up an old 14" monitor at Goodwill for $2.00. It worked. I
removed the flyback transformer for HV experimentation.

I hooked up a 9 volt battery on the input and setup a small gap
between the HV output and hv return. I though a momentary 9v pulse
would produce an observeable spark on the output. No such luck.

Any suggests?

Bob

I am not a TV repair expert, but the flyback transformer may be
powered from a higher voltage supply. 9v may be producing a few
thousand volts but not enough to make a spark. You need around 10kV to
see a good spark.

Other things I remember about flyback transformers:
They are very low output power.
They are self resonant so they are not just a simple transformer.
The circuits for creating your HV supplies using old flyback
transformers always start by winding a new primary and do not use the
primary on the coil.

Try searching the web for high voltage and flyback. There are a lot of
circuits out there that people have built.

Bob,

Use the Horz driver circuitry that was in the original monitor as its tuned
to the correct freq. The transformer works best at that freq and will have
the proper driving signal. Caution though as these devices are not toys by
any means. I used to work on TVs and have the most respect for these
circuits. There is the smell of corona and there is the smell of burned
flesh.
A jacobs ladder is always fun to experiment. I would recommend reading the
caution posted on the inside of the monitor when it comes to working with
these voltages.

Dave

Dave,

I pulled the flyback from the board. It dropped it from my workbench
when my cat jumped up. I just noticed the magnetic core is now
cracked. Good thing it was only $2.00.

The reason I didn't use the Horz circuit was that I was just trying
to experiment with a different supply.


Bob


--- In Electronics_101@..., "David Balma" <balma.d@c...>
wrote:

Bob,

Use the Horz driver circuitry that was in the original monitor as

its tuned

to the correct freq. The transformer works best at that freq and

will have

the proper driving signal. Caution though as these devices are not

toys by

any means. I used to work on TVs and have the most respect for these
circuits. There is the smell of corona and there is the smell of

burned

flesh.
A jacobs ladder is always fun to experiment. I would recommend

reading the

caution posted on the inside of the monitor when it comes to

working with

these voltages.

Dave

I picked up an old 14" monitor at Goodwill for $2.00. It

worked. I

removed the flyback transformer for HV experimentation.

I hooked up a 9 volt battery on the input and setup a small gap
between the HV output and hv return. I though a momentary 9v

pulse

would produce an observeable spark on the output. No such luck.

Any suggests?

Bob

I have seen several circuits as you have described. I plan to try
and open up the plastic flyback housing and see if it is possible to
add some primary windings easily.

The horz circuit from the original board was too complicated for me
to figure out an easy way of removing it. So the adding windings and
making an oscilator circuit may be a more practical solution.

I may pick up another monitor (to remove the flyback and be more
careful no to not damage it) and also look at an old microwave oven.



--- In Electronics_101@..., "manifold" <manifold_1@y...>
wrote:

--- In Electronics_101@..., "rsnyder187"

<rsnyder187@y...>

wrote:

I picked up an old 14" monitor at Goodwill for $2.00. It

worked. I

removed the flyback transformer for HV experimentation.

I hooked up a 9 volt battery on the input and setup a small gap
between the HV output and hv return. I though a momentary 9v

pulse

would produce an observeable spark on the output. No such luck.

Any suggests?

Bob

I am not a TV repair expert, but the flyback transformer may be
powered from a higher voltage supply. 9v may be producing a few
thousand volts but not enough to make a spark. You need around 10kV

to

see a good spark.

Other things I remember about flyback transformers:
They are very low output power.
They are self resonant so they are not just a simple transformer.
The circuits for creating your HV supplies using old flyback
transformers always start by winding a new primary and do not use

the

primary on the coil.

Try searching the web for high voltage and flyback. There are a lot

of

circuits out there that people have built.

--- In Electronics_101@..., "rsnyder187" <rsnyder187@y...>
wrote:

I have seen several circuits as you have described. I plan to try
and open up the plastic flyback housing and see if it is possible to
add some primary windings easily.

No! Do not damage the housing. There is nothing you can do inside
there except break the insulation and wire. The secondary is on the
outside layer.

Put the extra winding on the ferrite core. These extra primary
windings are usually added on the core opposite from the current windings.

BTW, did you say you dropped it and cracked the ferrite? If so, it's
ruined if there is much of a chunk missing. You may get some use from
it, but I would not count on too much.

If it is a minor chip, don't worry about it.

Keep in mind that you are talking about generating lethal voltages
which can jump several inches through air, or travel -much- greater
distances along something as innocuous as a chunk of wood.

Alien Steve

Alien Steve

The flyback has a ferrite core going down the middle of the windings
and extending outside to form a large 0. This large 0 is made with a
split which is held together by a large U shaped spring clamp. Is the
external portion where to wrap these new primary windings around?

The crack (from falling form the workbench) is the ferrite and is all
the way through. The large U clamp keeps it still in one piece. Do
do think it would be ruined?

Bob

--- In Electronics_101@..., "Steve" <alienrelics@y...>
wrote:

--- In Electronics_101@..., "rsnyder187"

<rsnyder187@y...>

wrote:

I have seen several circuits as you have described. I plan to

try

and open up the plastic flyback housing and see if it is possible

to

add some primary windings easily.

No! Do not damage the housing. There is nothing you can do inside
there except break the insulation and wire. The secondary is on the
outside layer.

Put the extra winding on the ferrite core. These extra primary
windings are usually added on the core opposite from the current

windings.

BTW, did you say you dropped it and cracked the ferrite? If so, it's
ruined if there is much of a chunk missing. You may get some use

from

it, but I would not count on too much.

If it is a minor chip, don't worry about it.

Keep in mind that you are talking about generating lethal voltages
which can jump several inches through air, or travel -much- greater
distances along something as innocuous as a chunk of wood.

Alien Steve

--- In Electronics_101@..., "rsnyder187" <rsnyder187@y...>
wrote:

Alien Steve

The flyback has a ferrite core going down the middle of the windings
and extending outside to form a large 0. This large 0 is made with a
split which is held together by a large U shaped spring clamp. Is the
external portion where to wrap these new primary windings around?

Yes.

The crack (from falling form the workbench) is the ferrite and is all
the way through. The large U clamp keeps it still in one piece. Do
do think it would be ruined?

Probably fine for your purpose. I would not put it back in a TV or
monitor and expect it to work, but for experimenting with high voltage
you won't be running it at anywhere near its full power so it will
probably be OK.

Alien Steve

Steve,

I took apart (sawed and pryed etc) the flyback just to see how is is
constucted.

I purchased another old $2 monitor. I removed the CRT and made a
Jacobs Ladder. The idea came from this website


My next step will be to remove the flyback from this old Radioshack
color montior. It has what I think is a seperate Hv rectifier -
square cube about 1"x1"x1" that is located after the flyback and
before the ctr.

Bob




--- In Electronics_101@..., "Steve" <alienrelics@y...>
wrote:

--- In Electronics_101@..., "rsnyder187"

<rsnyder187@y...>

wrote:

Alien Steve

The flyback has a ferrite core going down the middle of the

windings

and extending outside to form a large 0. This large 0 is made

with a

split which is held together by a large U shaped spring clamp. Is

the

external portion where to wrap these new primary windings around?

Yes.

The crack (from falling form the workbench) is the ferrite and is

all

the way through. The large U clamp keeps it still in one piece.

Do

do think it would be ruined?

Probably fine for your purpose. I would not put it back in a TV or
monitor and expect it to work, but for experimenting with high

voltage

you won't be running it at anywhere near its full power so it will
probably be OK.

Alien Steve

You really need a glass or plastic tube to put around your ladder.
That way, the hot air from the arc rises, carrying the arc with it.

Regards,
JJ