|
|
Post by Gary Lecomte on May 20, 2014 15:26:14 GMT -8
Since I Never had to BUY it, I'm Guessing that it is Probably the 410 Type.
I have rolls of Nomex in .002, .0035, .005, .009 Inch Thickness.
All Given to me by a Transformer & Motor Rebuild company a few years ago that I did previous business with.
They also supplied me with 8 Pound rolls of Enamel wire ranging from 18 to 40 AWG sizes at really good prices.
Nice to Have Friends in Good Places!
|
|
|
|
Post by Dr. Tournesol on May 20, 2014 20:07:03 GMT -8
Dear Lamazoid and Gary,
What can I say?
WOW.
Thank you so much for the thorough answer. I didn’t mean to inflict such so much writing work on you, and didn’t expect such an elaborate account. Certainly there is a lot to learn from you, both.
I will do some homework now, and, with your permission, I’ll reserve rights for further questions in the future. After all, one of my greatest pleasures in life is learning.
Thank you once again,
Dr. Tournesol.
|
|
|
|
Post by tournesol on Aug 2, 2014 23:23:00 GMT -8
Dear Gary and Lamazoid.
I hope I can still post questions regarding the two basic versions of the stun-guns.
1. In Lamazoid's stun guns, one of the most important components is the charge arrestor. In one design you use 1400V and the other 2500V. My question is: does the design of the inverter stage yield the necessary voltage to open the arrestor? In the first design you use full wave bridge, which I guess must deliver the voltage to above threshold. When I constructed few of these inverters the output ac was some 400V, and thus, I am afraid that the DC output after the bridge will not be high enough to open the arrestor. In the second design (the one that makes use of a 555 multivibrator, there is not even this bridge. Does this mean that I should get more than 2500 V directly from the inverter stage?
a. Also, there are two other components in this scheme that I do not understand their functionality:
i. The 3300nF 2KV cap between one of the inverter’s outputs and the input of the bridge.
ii. The two 27 MOhm resistors in this design, or the 10M Ohm resistor in the other.
2. In Gary Lecomte’s circuit for T2 testing there are two cap’s. One, C2 rated 0.047F and the other, C1, 0.01 F. Can you please explain their functionality in the circuit? Or, alternatively, why did you not include another 0.047F to the circuit to get a symmetrical input?
Thank you in advance for any answers and clarifications,
Yours,
Tournesol
|
|
|
|
Post by Gary Lecomte on Aug 3, 2014 5:48:19 GMT -8
2. In Gary Lecomte’s circuit for T2 testing there are two cap’s. One, C2 rated 0.047F and the other, C1, 0.01 F. Can you please explain their functionality in the circuit? Or, alternatively, why did you not include another 0.047F to the circuit to get a symmetrical input?
***** SEND ME A LINK to this Project!
I Can't seem to find it now.
The .01 is to help Reduce NOISE from going Back into the power Lines.
As to the .047 uF NOT "F" Mainly it Limits Current to the Coil.
Since it is a Single Coil, Not sure what you mean by symmetrical input.
|
|
|
|
Post by lamazoid on Aug 3, 2014 8:11:42 GMT -8
Dear Gary and Lamazoid. I hope I can still post questions regarding the two basic versions of the stun-guns. 1. In Lamazoid's stun guns, one of the most important components is the charge arrestor. In one design you use 1400V and the other 2500V. My question is: does the design of the inverter stage yield the necessary voltage to open the arrestor? In the first design you use full wave bridge, which I guess must deliver the voltage to above threshold. When I constructed few of these inverters the output ac was some 400V, and thus, I am afraid that the DC output after the bridge will not be high enough to open the arrestor. In the second design (the one that makes use of a 555 multivibrator, there is not even this bridge. Does this mean that I should get more than 2500 V directly from the inverter stage? Sure it does. More of it, because inverter circuits (both of them) have no voltage feedback, or any other requlation, surge arrester actually "cuts" voltage, preventing it to rise above critical values. Measuring inverter output voltage is practially useless due to several reasons: -multimeters are not rated to measure HIGH FREQUENCY AC, and will error (if it won't burn completely, i've killed many of them that way in my early experiments, ha-ha) -push-pull inverter output varies depending on load an power supply (cause it's self oscillating unstabilized type) - flyback inverter (with 555 ic) due to it's physics can output (theoretically) UNLIMITED voltage. Practically, this is limited with transformer winding resistance, and semiconductors breakdown strength. But even in this exact circuit, if you remove 2500v arrester, the voltage wil easily rise up to 5000v and MORE, with the same number of turns! It will rise until something (more likely - load capacitor) burns. AND it often burns diodes, so special HV diodes rated at 12,000v (from TV multiplier) are used. Also, If you just turn flyback on with open ends (with no load), the voltage will rise and MOSFET will burn, because of "reflected voltage" which transforms from secondary to primary while the switch is closed. Because unloaded secondary voltage rises very high, it's almost 100% guarantee that "reflected" voltage will exceed MOSFET breakdown limit. Transformer windings in this circuit are calculated to avoid this during normal operation when arrester CUTS voltage to nearly 2500v. (from my experience, EPCOS arresters are very precise for this kind of devices, and if it says 2500v - it's 2500V +- 50V MAXIMUM, even with high frequency (100-200Hz) discharge) a. Also, there are two other components in this scheme that I do not understand their functionality: i. The 3300nF 2KV cap between one of the inverter’s outputs and the input of the bridge. ii. The two 27 MOhm resistors in this design, or the 10M Ohm resistor in the other. 2. In Gary Lecomte’s circuit for T2 testing there are two cap’s. One, C2 rated 0.047F and the other, C1, 0.01 F. Can you please explain their functionality in the circuit? Or, alternatively, why did you not include another 0.047F to the circuit to get a symmetrical input? The 3300 pF (PICO FARAD, not nano) cap limits the current surge when capacitor STARTS charging. This, in its turn, has influence on oscillation frequency and generated power. Also, it acts as DC blocking capacitor. This is very simple circuit on the first look, but everything here is interconnected. So we can say, in simple words, that it stabilises operation mode, and improves efficiency. Actually, the value of this capacitor should be picked depending on power supply. 3300 pF value was used with very old (available at the moment of publication, in 2006) Ni-Cd batteries. With modern high-current grade Ni-Mh of Li-Po batteries, it should not exceed 470pf in most cases. ii. Two resistors were used with the purpose of "balancing" capacitors. In early experiments with red chinese caps, they have frequently EXPLODED, and putting resistor on EACH cap solved the problem. Later practice has shown that good quality capacitors does not need that, one resistor is more than enough for the main purpose of discharging caps after circuit turns off. So, the first ediditon of circuit has two resisotrs just "for the worst case" )))) \Hope this helps... |
|
|
|
Post by tournesol on Aug 3, 2014 23:14:35 GMT -8
Dear Gary and Lamazoid, Thank you so much for the rapid and insightful responses. I do learn quite a bit each time. As to Gary’s question: the diagram (attached) contains two SCRs. The T-Primary current vs. time graph presented at the above right corner show that the primary is injected with alternating triangle-shaped pulses, positive and negative in consequence. I thought that this is realized by alternating opening of the two SCRs (the above and the lower ones. However, this limiting current cap (C2) is connected only to one input of the primary (the above one, in this diagram). Now, that I am thinking about it, since the primary is connected in series with the cap, it does not make sense to add another one (below), and the same cap limits the current in both positive and negative pulse. Please comment if I am wrong. I have another question regarding Lemcote’s “stun gun 2” circuity. As you can see in the diagram, between the first and the second multiplier diodes, you placed a cap, of 0.05mF that goes to the commonground. What’s its purpose, and is there a reason to optimize its capacity? In some experiments, I found that omitting this cap altogether increases the voltage output of the multiplier. Wors, in some cases, it seemed that this cap shunts the output current to below acceptable levels. What do you think? Thanks, again, for the support and education. Dr. Tournesol   |
|
|
|
Post by Gary Lecomte on Aug 4, 2014 9:25:20 GMT -8
Not Sure Why the .05uF cap is decreasing your Output.
It Should Increase it.
Is your .05 cap rated at a High enough Voltage?
But you can leave it out if it works better for you.
RE: I have another question regarding Lemcote’s (WRONG) “stun gun 2” circuity.
Why not just say Garys circuit.
Take care.....Gary
|
|
|
|
Post by tournesol on Aug 6, 2014 20:28:34 GMT -8
Thanks, Gary.
Sorry for the misspelling.
Take care.
Dr. Tournesol.
|
|
|
|
Post by KevinK on Feb 16, 2018 15:34:24 GMT -8
I’ve read this thread over a few times. Been looking over the science behind these for the past year after being dissapointed with the cheap eBay stun guns, and even a U.S. made Nova one.
I have a few quick questions and I hope not to annoy anyone by them.
Could you use a SPW-80 Inverter transformer that are used in LCD TVs with a modified primery set up with a center tap for a T1?
I believe the T1s in the Nova and others are a bit underpowered. I was going to use the T2 out of it, but after reading this I might not be able to..
Also, wouldn’t using trench mosfets be beneficial in a stun gun circuit?
|
|
|
|
Post by KevinK on Feb 16, 2018 15:39:43 GMT -8
|
|
|
|
Post by Gary Lecomte on Feb 16, 2018 18:48:29 GMT -8
Looks like a Typical Stun Gun. |
|
|
|
Post by Gary Lecomte on Feb 16, 2018 18:52:29 GMT -8
I’ve read this thread over a few times. Been looking over the science behind these for the past year after being dissapointed with the cheap eBay stun guns, and even a U.S. made Nova one. I have a few quick questions and I hope not to annoy anyone by them. Could you use a SPW-80 Inverter transformer that are used in LCD TVs with a modified primery set up with a center tap for a T1? I believe the T1s in the Nova and others are a bit underpowered. I was going to use the T2 out of it, but after reading this I might not be able to.. Also, wouldn’t using trench mosfets be beneficial in a stun gun circuit? I Have No Knowledge on that Inverter Transformer. And Not sure What a TRENCH Mosfet is or their specific Applications. I have had No Problems just using an IRF640 or IRF740. |
|
|
|
Post by KevinK on Feb 16, 2018 19:31:39 GMT -8
Trench mosfets, from what I have read, has the lowest ON resistence compared to others. as far as the inverters, where is an underside of one I’m referring to.  Doubt that really helps you though.. |
|
|
|
Post by Gary Lecomte on Feb 16, 2018 20:51:17 GMT -8
That looks like a Reasonable HI Voltage FLYBACK Transformer.
Most of the Mosfets I use are just a Few MiliOhms.
Such as a STP75NF75
|
|
|
|
Post by lamazoid on Feb 18, 2018 12:07:55 GMT -8
hello Kevin. can you make some more hi-res photos of NOVA-XR5000 for my collection? i collect commercial stun guns (mostly russian) here: ecdinside.info/and i have there an article about XR-5000 by Theodore Bernstein: ecdinside.info/статьи/исследование-nova-xr-5000/that was a (historically) first law enforcement stun gun, that were the times when noone had a clue what exactly it is, and how it works. The article explains how traditional knowlege about electric shocks could be applied to estimate stun gun harmness. photos would be good addition to that. pls reply to me via PM (personal message) or email. as to your main question, i think that CCFL transformer is bad choice. it's rated for high frequency, very low current, and has high DC resistance. fortunately, there are many easier ways to construct a stun gun at your kitchen, if you really need it  check Gary's articles 1 and 2 : chemelec.com/Projects/Stun-Gun-1/Stun-Gun.htmchemelec.com/Projects/Stun-Gun-3/Stun-Gun-3.htmalso, one of our members had recently submitted a thorough guide on powerful (actually, VERY powerful) stun gun: chemelec.com/Projects/Stun-Gun-3/Stun-Gun-3.htmthat is written especially for newbies without any knowlege of electronics. atricle is in russian, but pictures tell the story better than words  ecdinside.info/статьи/novokainum/of course, feel free to ask any questions here |
|
