Tester box

[TaylorW]

I just got this new tester box that shows you if your foils are working. and there is a red a green button. so when i hook it up the red lights up. I am wonder what that means and what the green means to.

[neevel]

The standard set up of lights on a two-led tester is:

red = closed circuit between B and C lines.
green = closed circuit between A and B lines.

For foils, you want the red light on when the weapon is in its normal state, and the red light off when you depress the tip. You should never see a green light with foil (if you do, then you've got a short in the body cord you're using to test the weapon).

For epee, you should see the green light go on when you depress the tip, and off when you release it. If ever see a red light with epee, it means that you've got a short in the weapon to 'ground' (C-line).

-Dave Neevel

[TaylorW]

when i press my tip to the ground the red light goes off. is that right.

[neevel]

Yes, that's what should happen. The normal state for a foil is a closed circuit from B to C. When the tip is pushed in (against an opponent or the floor) the circuit is broken (which would cause the LED on the test box to go dark).

-Dave

[cleghmor]

Neevel

I , this is sorta on topic. Do you have any schematics to make a buzz box. I'd like to make an epee box that will buzz when the tip is depressed . I went to radio shack and bought a buzzer and and a little box. What now? Any ideas will be welcomed. I would like to use a 9v battery, I have the banana plugs, buzzer and an assortment of resistors ( I don't know if I'll need those) I don't really think a light is needed...........

clegh

[neevel]

The main thing I can think of is a timer chip that will latch 'on' and deliver current to the buzzer for a set period of time whenever it sees a closed A-B circuit before turning off again-- you'll probably also need to use a transistor as your 'actuator' (can you tell I'm really a controls guy?) to switch the current to the buzzer. I wouldn't be entirely surprised if you could find a 'canned' IC that accomplishes this at Radio Shack. If you wanted to go really crude, you could just build it so that the epee is acting as a push-button switch between the + lead of the battery and the buzzer, with the - buzzer lead going straight to the battery-- this would give you a momemtary buzz only for so long as the epee tip stays depressed.

-Dave

[cleghmor]

Neevel

Crude is my middle name. Thanks for the info.

clegh

[eternal109]

I've heard of doing something along the same lines using the scoring box and garage door openers, that you you have a remote system that sets off the scoring box. Just wondering if anyone has a clue as to how to set it up?

[flik]

a guy in my club has made 6-8 of the buzz boxes already... i'll get on his case to get the schematics. they cost about $10 to make.
drop me your mailing addy and i'll get them out to you.

[Dogstar]

If you touch the body cord lame clip to the foil you should get the green light at the same time the red is on and if you depress the foil tip with the lame clip then you should get green and the red should go out. You can connect the clip on your lame and check for dead spots this way also.

[oiuyt]

Is there anywhere to get the plugs other than by disassembling broken cords or whatever? how about the holes that the plugs go into (other than disassembling sockets)? Okay, I don't really mean the HOLES per se, but the metal things that are like boltss with a hold down the center.

I've tried various hardware stores and what not and they're all like "uhhhh... WHAT'S that used for again?"

In a somewhat related question does anyone know of a source for screws to replace the screw on the side of a bayonet socket? My club has nearly a dozen sockets that are missing that one little screw and would be perfectly good other than that.

Thx.
-B

[neevel]

You can purchase plugs and plug pins from fencing suppliers (the Fencing Post, for example, give prices for Prieur and Uhlmann plugs and pins on their site). For 3-prong and the C-pin on 2-prong plugs, the diameter is the same as standard bannana plug connectors, so you can just purchase individual sockets at Radio Shack or the like. The spacing for the 3-pin plugs is A pin offset 1.5 cm from the B (center) pin, and C pin offset 2.0 cm on the other side from B. For a test box, you just drill holes in the casing at the appropriate separation and bolt down the BJC sockets.

I actually don't know what size the screw is for LP bayo sockets and I've never seen any of the suppliers selling them. Depending on how good your local hardware stores are, you may be able to bring an example in and have them determine the size and threading for you (I really should remember to do that myself sometime, just to know). It's probably something like metric 2mm, but given that it's Leon Paul it could be an English thread size (it's smaller that 4/40, which is usually the smallest size machine screw that most hardware stores stock).

-Dave Neevel

[Craig]

Here's a URL for a test box sketch.

http://www.roman.net/~fspratt/afa/testbox.html

Cheers,
Craig

[oiuyt]

I tried a local radio shack for the pins and sockets on the assumption that they MIGHT be similar to accoustic stuff and just got some funny looks, a little scrounging around the store and no results.
I guess I'll try another one.
-B

------------------
"Oh but you can't expect to wield supreme executive power just because some watery tart threw a sword at you!"

[neevel]

A clarification-- by the pins and sockets, I was referring to what you would use to make a test box. The individual tines on 3-pin plugs are the same size as standard Bananna Jack plugs (male and female) that you can find at any Radio Shack (they'll be in or near the section with test leads for ohmmeters and electronic components, not the audio cable area). If you're looking for complete plugs or sockets (2-prong, 3-prong, LP bayo), those are fencing specific items and will only be found at fencing suppliers. The only weapon socket that was a current standard electronics connector was the capteur socket on early electric sabres, which was a BNC plug.

-Dave Neevel

[BarryTice]

I've put together a schematic for a foil buzz box. You can get the PDF file at http://www.pointcontrol.com/foilbox.pdf if you want it. All the parts are available at Radio Shack (or the like). It runs on a 9-volt battery, pulling less than a milliwatt when it's not going off. Just make sure you put a good on/off switch on it, or you'll wander what that beeping noise coming from somewhere is. As the instructions go, it beeps for 1 second when your foil tip is pressed, then stops. (It's great for testing springs for weight.) The instructions tell how to change the duration of the beep, if you want to.

I've also seen a schematic available for an epeé box. (It's not mine and I haven't tested it, nor even looked too hard at it, so I don't promise it will work. I just use the continuity tester on my multimeter for epeés.) You can find it at ftp://128.113.110.117/Anonymous/fencing/Epee_Test_Box.PDF if you're so inclined.

Hope these help.
-- Barry Tice

[nritter]

I've been designing a tester/buzzer box that works for both foil and epee. I'm still in need of one more bit of information before the design is complete.
I'm aware of a recent FIE rule change that requires the foil tip to be depressed for a certain amount of time before a touch can be scored. Can somebody tell me how long this time-delay should be?

Thanks,
Nathan Ritter

[tsalyards]

Time delay? I don't see how that would work with the current technology. The circuit is either open or closed and the spring dictates pressure, not timing. I am curious to see if that is the case as I am not an armorer.

-Tad

[neevel]

The FIE regs for foil time sensitivity are that the machine must always register a break of 5 ms and always reject a break of < 1 ms. There was a change in the rules to mandate a minimum break of 8-10 ms for a touch to register to reduce the likelihood of flick hits landing, but that has since been rescinded in favor of development of a new foil point with a minimum travel requirement and possibly a heavier pressure spring. Hence, the old limits stand.

Eric Schlaepfer sent me firmware for my Eigertek machine which had the proposed longer tip debounce time-- it doesn't make much of a difference, so it's easy to see why the FIE's moved towards the route of changing the foil tip.

You can find the relevant specifications in Appendix B of the current on-line rulebook.

BTW, Nathan, the Favero tester incorproates a pair of yellow LEDs which will momentarily flash if a state-change that lasts under 1 ms occurs. They're handy for indicating any naescent problems that aren't yet bad enough for a scoring machine to notice. Don't know if Favero has a patent on that or not.


-Dave Neevel

P.S.-- I took a LP Bayo socket and foil plug into a hardware store. The screw on the socket is 2/56 thread. I didn't find an exact match for the plug contact screws, but 3/38 is close enough, though you might need to use a bit of blue Loctite to keep them from loosening.

P.P.S.-- Tad, debounce times (i.e, ignore a signal that's shorter than some minimum duration) are a very common thing in any
electronic device or system-- otherwise you can get false-reactions to noise and random blips that are always present to some degree. At work I deal with them all the time in the design of HVAC controllers and applications.
The scoring machine specs were originally made with the response times of electromechanical relays in mind. Since all modern scoring machines are essentially a microprocessor examining the state of the various input lines and then computing an appropriate response, it's simple to program in any desired timing.

[nritter]

Thank you for the information Dave. I'm glad to here that the FIE has NOT adopted this new 8-10ms "debounce" (anti-flick) timing. I'm against this new FIE timing requirement for two reasons; 1) I'm an avid flicker and 2) It was making the design for my buzzer/tester box more difficult.

Cheers,
Nathan Ritter