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SGE · 08-05-2007, 11:53 PM

Hi,

I found my old bread board from college and I would like to make an epee buzz box. However I need help from someone who knows about electronics. Yes, I know I can buy one, but I want to make one.

I found, after an extensive search, schematics for one. The problem with the design is that it buzzes, not when the tip is pressed down, but as it comes back up. Also, if the tip is pressed down for a while it doesn't work (I am assuming the capacitors drain, but since I wasn't an electrical engineer major that is just a guess). So what I am looking for is:

1. Schematics on how to make an epee buzz box. (For example, telling me to get a 555 IC chip and research it does not do me much good as I am not that well versed in electronics)
2. The box buzzes when the tip is pressed down, not on the spring back.
3. It continues buzzing as long as the tip is pressed down.
4. The parts are available (for example: a 731 microfarad capacitor may be theoretically possible, but I cannot buy one)
5. The buzzer buzzes for at least one second once the tip is depressed.

Your help will be appreciated.

Thanks!

KD5MDK · 08-05-2007, 11:59 PM

Well, the obvious answer is to have the power to the buzzer come in the A line and out the B line (or vice versa). It will then only have a completed circuit when the tip is depressed. Of course, this could make the buzz a bit brief to be noticed.

pgillard · 08-06-2007, 08:54 AM

I have made a few little buzz boxes that automatically select between foil and epee, and use only three components - an 8 pin Atmel processor, a resistor, and a tiny speaker. The main problem with building one is that you need some way to program the processor. (I built it this way because the processor is actually cheaper that the 555 timers required to get the correct timing.) If you are interested, pm me and I will send you a circuit and the code.
It doesn't do exactly what you want, by the way (continue buzzing while the tip is depressed), it implements the actual epee and foil timings, and buzzes (or plays a few notes of music) for 2 seconds after the hit.

larkmaj · 08-06-2007, 09:49 AM

Epee Practice Buzzer Schematic

fencerbill · 08-06-2007, 06:57 PM

What is the best buzz length? Thinking way back to my Epee lessons, at least 8 years ago.

Wouldn't you want to be able to hear separate buzzes for the pick to the wrist and then the follow to the chest?

I should think about between 0.1 and 0.2 seconds duration would be good. Definitely longer than the duration of the tip depression, IMO.

SGE · 08-06-2007, 11:18 PM

pgillard,

I am definitively interested in your design. If you could send it to me at fencing_eddie@yahoo.com I would appreciate it very much. I am not sure if I'll be able to do it, but I am sure interested!

Thanks!

SGE · 08-06-2007, 11:26 PM

larkmaj,

Assuming I assemble the circuit correctly on my bread board, the design to which you sent me the link goes off not when the tip is depressed, but when the tip springs back. Also, if the tip is depressed for about a second, the buzzer won't go off. I am assuming that the capacitors get drained. Then again, maybe I goofed when I assembled the circuit...

larkmaj · 08-07-2007, 08:10 AM

Quote:

Originally Posted by SGE

larkmaj,

Assuming I assemble the circuit correctly on my bread board, the design to which you sent me the link goes off not when the tip is depressed, but when the tip springs back. Also, if the tip is depressed for about a second, the buzzer won't go off. I am assuming that the capacitors get drained. Then again, maybe I goofed when I assembled the circuit...

This buzzer goes off when the tip is depressed (A and B connected). There is a slightly different circuit I think I have somewhere where the buzzer goes off when the 2 lines are disconnected (for foil, B and C lines). I think I still have mine assembled on a breadboard at home so I will double check it when I get the opportunity.

RPI Epeeist · 08-07-2007, 11:04 AM

If the one larkmaj gave you is the one I'm thinking of (which it is) then I have a working model of it in front of me and it does buzz when depressed, holds as long as you've depressed and upon release will begin the rest of the duration of the buzz. So yeah, double check that you've set it up correctly.

SGE · 08-08-2007, 12:37 AM

Well, I built the circuit about 3 time with the same result. I would go off on the spring back. So I decided to move the chip to a different part of the bread board and rebuild the circuit one more time. It worked great! So I either made the same mistake 3 times or I managed to pick the one screwed up part of my bread board.

Thanks for all the help!

RPI Epeeist · 08-08-2007, 03:05 AM

Sometimes all it takes is to start all over again. I took that circuit you just made, bought a little project box, drilled 3 holes in it, stuck 3 body chord prongs through the holes, glued them in placed and wired it all up and made a buzz box like you'd see for sale... faveros go for about 40... I made mine for less than 10. Worth it? I'd say so!