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Required Privare Messages?

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HarveyH42

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I get one every week or so, and usually don't know what to do with them. I don't want to be rude and just ignore them, but most of the time these messages would be more appropriately posted in the forum (isn't that the point of this website?). Wish there was some sort of PM filter or way to restrict to people invited. Turning off PMs isn't a good idea, as discussed many times since the 'unfortunate' insudent... Anyway, figured I'd put my bit first, it was a very long message.

leonar said:
0. The transistor used here is as a switch that on and off repeatly. What is the ideal freq. of this on & off?
1. The transistor used here is as a switch that on and off repeatly, so it is only produce pulse DC ( no negative pulse). Is it as good as the pulse that has negative pulse ( for example: pure sinus wave)? How about the efficiency between them?
2. The trafo used in this thread probably rare to find and have thin wire, that make me care the thin wire will broken when i apply about 500mA current. So, i will use regular household adaptor that is easily founded, 3V at the primary and 240V at the secondary winding, rated 500mA. Is it OK? Or maybe have to be rated 1A?
3. If above regular trafo is used, which freq. is suitable that generate by the 555 (at pin 3)? Is it 50/60Hz?
4. Is there more suitable trafo beside above regular trafo?
5. What's the function of D1 (4148)? Is it safe if it's not used?
6. What's the function of D2 (4005)? Is it safe if it's not used?
7. If i use 6V as the input to the 3V (written on the trafo) input for above trafo, i will get 480V (240V x2) at the output. Is this right?
8. What are the rules so that the output can show arch/spark jump (i want just only 1mm gap). What is the minimal volt and minimal ampere at the secondary trafo?
9. I wonder the pulse that generate by the 555, has it negative pulse (eg. 5V, 0V and -5volt) or only positive pulse (eg. 5V and 0volt)
10. Is it needed to put capacitor (for example: 10uF/400V) at the secondary of trafo? or maybe up to 20 capacitors @10uF/400V paralled? just to make more painful.
11. If capacitors above is attached, what rectifier is best? Halfwave or full wave rectifier?
12. Can voltage multiplier ( a diode and a capacitor) used at the output? Is it possible?
13. If the output is shorted to make spark, will this action make the component like transistor, or trafo , or IC555 broken?
14. To make more painful, i've maybe crazy idea. Why just make 2 or more unit of this thread's project. But all are powered by same power supply. If for example, we make 2 unit, we have 2 independent output (from trafos), right? I think It's clever to put these 2 output in series, so if for example, one output is 480volt, by putting in series, we got 960volt (480V x2)
15. I also interested in the swatter ( electro racket to stun mosquito/flies)
-It use just only a transistor and a resistor for providing oscilator, is full sinus is produced by this oscilator?
16. I also interested in the swatter ( electro racket to stun mosquito/flies)
-At the secondary side (where the big capacitor is), a diode (halfwave rectifier) is used, i think this is not eficient, and i plan to replace with fullwave rectifier (4 x 1N4007). Can you give comment about this?
17. How much does TIP31 cost? Is it expensive?
18. There are also TIP31A/B/C , what's the difference with TIP31?
19. Can you suggest "alternative transistor" for TIP31 that maybe cost cheaper?
20. I'm very interested in stunner / spark generator. If i only use 2 AA NIMH battery that each has 1,2 volt 2400mAh, so the total voltage is 2,4volt, can i make strong/deadly stunner? any idea? May be by increasing the capacitors at the output, or use voltage multiplier ( diode and capacitor), or by making many unit and series the output from each trafo. Can you suggest ultimate posibilty strongest stunner, by using only 2,4V ( form 2 NiMH battery)
21. If only use 1 NiMH battery that has voltage 1,2volt 2400mAh, is it posible to make medium stunner?
22. Out of topic, if we compare small adaptor trafo ( for example: 100mA,200mA, 500mA) with larger ampere adaptor trafo (for example: 1A, 5A, 10A trafo). Do they have difference in efficiency? Is larger the ampere of the trafo, the efficiency is better? maybe because of the bigger the diameter of the copper wire of the trafo, the resistance is also decrease, so the resistance loss is smaller. I've also same Nokia handphone adaptors, they have the same size, but the weight is not the same.When in use, the one is hotter than the other, can you explain this?
 
I also received that message.

This is how I normally respond to these kind of messages, it's one of my canned responses:

Please ask on the open forum, so you can have the benefit of others who might be more knowledgeable than me. Also others might benefit from the advice I might offer you.
 
I also got the same PM. I told him the project is a child's toy and he should make something more useful.
 
So, instead of posting a thread, we get a mass-mailing. I wouldn't mind changing my ranking to 'new member', just to avoid being targeted. I don't have a broad knowledge of everything electronic, just remember what I've seen or worked with.
 
I'm just rude; I don't usually reply. I like Hero's response, though, and will perhaps use that next time. I agree, this forum is for helping others, and it bugs me when someone wants the info sent to a private mailbox, which won't ever reach, or help anyone else. I'm sure there are people who just come and read, and learn, and hardly ever ask questions.

I don't have a broad knowledge of everything electronic, just remember what I've seen or worked with.

I'm the same way. :)
 
I suppose it must work somehow, look at email spam - people wouldn’t do it if it didn’t work?

So too, as unfortunate as it sounds, 'double posts' probably do have better chance of getting replies. Not from the everyday readers of the forum, but from the majority of who visit this forum - complete strangers. Take a look on the home page how many members there are too guests.

When I checked 26 members and 299 guests

Ease of communication is vital, but it allows all types to abuse its functionality :mad:
 
There are 10 times as many guests as there are members right now.
Too many school kids visit here.
 
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