Donald Smith Devices too good to be true

[Wistiti]

OK, latest build progress. How to mount the meters: go vertical! This took me more hours than I intended to fabricate, but it works. Still have to mount the meters on the HVM board. Also, having the metal rod this close to the HV section is not good. I need to get some nylon fasteners and threaded rod instead, it exists but not at the local hardware store....

Nice and clean build!
On my side I just came from the store with some cutting board.

[Wistiti]

flyback

@Mwtj can you please tell me to what kv the TFB4100ad is rated for? It seem to be bigger than the one I currently use... I think to change for this one if the spect are ok.
Thank you

[Mwtj]

HR8503.

If correct rated for 51.1kV

Open file on new tab.otherwise it is black.

[Wistiti]

HR8503.

If correct rated for 51.1kV

Open file on new tab.otherwise it is black.

do you mean the hr8503 is the same as my tfb4100ad?

if so 51,1kv is really nice!!!

i'll give it a try. thank you for your help and the nice diagram!

[Mwtj]

do you mean the hr8503 is the same as my tfb4100ad?

if so 51,1kv is really nice!!!

i'll give it a try. thank you for your help and the nice diagram!

hr8503 is replacement part for the tfb4100ad.

[Wistiti]

Partially finished the isolation of the hv side. I use cutting board piece and plastic spools. Brief the things I have around...
I have also replaced the flyback transformer and connected a dc/dc boost converter for the source of the zvs driver. So i will be able to start it with 7v to 12v and feed the zvs with a steady 30v.

[Wistiti]

Hvm

Hi guys!
What you think of this HV module?
https://www.amazon.ca/CNBTR-Power-Mo.../dp/B01969RF6C

[dragon]

Those are designed as a drop in module for hand held taser's - they pack quite a punch but I don't believe it would make a good unit for what your doing. They draw a considerable amount of power and are meant for short bursts, not continued use... fun to play with though...

[Wistiti]

Those are designed as a drop in module for hand held taser's - they pack quite a punch but I don't believe it would make a good unit for what your doing. They draw a considerable amount of power and are meant for short bursts, not continued use... fun to play with though...

Thank you Dragon for the reply!
I have think to use a serie of hv resistor at the output to reduce the power consumption of the module... Do you think it's a good idea?

I already order one so if it not good for this project, I will use it in an other one!

[dragon]

You might be able to regulate the input current easier than the output - in turn regulating output... experiment with the lowest current input it would operate on with a reasonable output.

[dragon]

I was going over some calculations on a project I'm working on and things didn't really add up - at least to my satisfaction...

Has anyone measured the capacitance between their ground and antenna connections? If you have the capability to do this I would greatly appreciate any numbers you could supply as a comparison to what I'm reading on mine.

Thanks...

[tswift]

I was going over some calculations on a project I'm working on and things didn't really add up - at least to my satisfaction...

Has anyone measured the capacitance between their ground and antenna connections? If you have the capability to do this I would greatly appreciate any numbers you could supply as a comparison to what I'm reading on mine.

Thanks...

Hmm.... interesting, and a bit tricky. Theoretically for a small wire suspended a significant height above ground it should be around 6 pF per meter. In practice it's going to be difficult to measure with an LC meter because all the meter does is measure the resonant frequency of a tank circuit, and with a capacitance that small, at least on my cheapo meter the resonant frequency is likely to be in the ballpark of the antenna 1/4 wave resonance at 500 KHz. It's easy enough to put the meter on it and find out what it says, mine should be around 900 pF (theoretically) at DC and frequencies significantly below the first resonance. The only way to get an accurate reading on it is probably an antenna analyzer, or at least a better LC meter that has selectable inductances. For reference:

http://www.pulsedpower.eu/toolbox/to...acitances.html

[tswift]

Sure enough, I can't get a valid reading on it at all. The meter just reads 0.00 pF. If you press the button to display the frequency it reads about 1.4 MHz, so it's looking around the antenna third harmonic and it's just completely confused. What kind of readings are you getting?

[dragon]

Mine is resonant at 2.4 Mhz (1/4) with a reading of around 300pf. I suspect the reading isn't completely accurate because there is a small amount of electrical activity, can't get around that. Just looking for a ballpark figure.

Calculating just the area and distance I get somewhere in the range of 1 pf, 55 pf similar to what you described above and a reading of 300pf. What I'd like to do is drop a pipe in the ground with an insulated rod centered in the pipe. It appears that I may have to build a capacitor in a steel box adjustable above ground...It occurred to me that something similar could be used above ground to simply adjust the height of the plate.

With the antenna/ground connection, Bruces design is simply charging a cap between 2 capacitive plates ( a cap in a cap as it were ). So, I started doodling different arrangements on my white board and came up with some interesting things I'd like to try.
.

[tswift]

What I'd like to do is drop a pipe in the ground with an insulated rod centered in the pipe. It appears that I may have to build a capacitor in a steel box adjustable above ground...It occurred to me that something similar could be used above ground to simply adjust the height of the plate.

This sounds interesting. Not sure what results you might obtain, but if we already knew everything then there would be no need to test! I think I understand what you are describing and I think there is at least some chance of producing the desired effects similar to the antenna. Obviously the antenna arrangement, even a much more compact one, isn't going to be practical for everyone everywhere. I think merely having the "capacitor in a capacitor" arrangement, so to speak, is one of those "necessary but not sufficient" conditions. I think that in order to produce the effect, some current must flow through the environment. It might be tiny, I measured it at 250 microamps, but some current is necessary so there will have to be some ionization happening around the inner rods. If they are completely insulated with no breakdown I don't think you will get anything. But I could certainly be wrong, I am not the jedi master, I am a mere padawan.