Test Box wish list

[LordShout]

I've been toying around with different test box designs in my head and have wondered what other armorers want on their test box? This is my verision of fantasty football so I'm not saying anything I draw will ever leave the realm of paper.

The one I've got sketched out right now has a seperate analog ohmmeter display for each of 3 lines. This allows for some fun features, first you can plug in a body cord and get seperate and simultaneous readings of the resistance down each line. You can also test up to three weapons at once using each meter seperatly. It's desinged to have ports for bayonet cords, two prongs, epees hardwired in but userservicable. It should also have the male ends of all the common cords hardwired into it. I've considered adding a wheatstone bridge for the extremely accurate measurement of static resistance. This would come in handy when testing lames and such.

Of course it would have the standard lights so that the box could be used without having to read and interpret analog measurements.

What else?

While I'm in fantasy land I'll mention some equipment I've had the chance to play with recently, its a digitial oscilloscope (list price 15k) that would quite simply rock as a test box. It can serve its results up online, can display resistance/current/voltage in near realtime (we're talking nanosecond twitches can be analyzed at your leisure, has a tenthousand point memory, it's quite the toy.

[SJCFU#2]

My current test box has four meters (one for each line plus one for lame testing) plus LED's to indicate shorts between A and B or B and C lines. Two of the meters can also be used for weapons testing. I had originally toyed with the idea of adding another two or three meters to measure resistance between lines (perhaps on a 1K scale, whereas the other meters all measure single ohms). I abandoned that idea when the whole thing started to grow to the size of a briefcase. I'm currently working on a replacement for my current box - ideally something more lightweight and compact (I figure that I'm already carrying enough tools - I don't need another case the size of a small toolbox just for meters).

[brtech]

Many tournament armorers have 3 ohmeter test boxes with all the sockets. Look for a thread about TournaTest to see my latest. I think a whetstone bridge is complete overkill; a simple ohmmeter with 5 or 10 ohms center scale is quite adequate.

Testing 3 weapons at a time is a pretty silly idea I think. What would you do with that? If one person is testing, you don't have enough hands. If three people are testing, they have trouble seeing the meters unless the box was huge.

Having lights is nice if they really detect shorts while you are doing the resistance checks. You need a way to detect shorts, however you do it.

If you are going to put in lights, do something like the Favero tester that has the intermittent lights.

A digital oscilloscope is a cool device, but not so practical for the problem.

I've thought about microprocessor powered test boxes with LCD displays. I've never made one for a couple of reasons. One is that the power supply problem is pretty annoying OR you need analog switches. The latter is a pain because the inexpensive ones have high resistance. You can probably calibrate that out, but it's annoying.

I'm also not sure an inexpensive LCD can display intermittents as well as an analog meter pointer can. Ted Li has a digital test box with three rows of LEDs. It does a pretty good job on intermittents, but after using it for a while, I still like the analog meters better. It does make a very small, very accurate cord tester though. And, BTW, the power supply IS a pain. It uses a DC to DC converter with three secondaries in order to get the shorts tests to work.

I think you will find that an "octopus" cord is a better way to get the male ends than building them in the box. Dan DeChaine makes the nicest of them, and of course, being a Dan project, it has plugs you probably never saw before. Mine has the usual 3 pin, 2 pin and bayo. I also have a Negrini on mine.

Other things to think about:
Big meters are good.

There is a tradeoff between center scale reading and current draw, which means battery life. If you have 5 ohm center scale, you really need D-cells. Shipping a box with D-cells is hard; you need a physical restraint, not just a high quality battery clip.

If you look at a lot of test boxes, one of the places you need to pay attention to is placement of the 2 pin sockets such that it's easy to plug in the cords quickly (when you are working a long line) and also the way you place the 2 pin socket so that the spring clip doesn't interfere with plugging in the plug.
Another thing you see a lot of ideas tried out is what you use for the lame/cord clips.

You may want to include a pair of banana sockets for a lame test set up.

[the ancient one]

If you want to play:

Before you spend $15,000 on a new oscilloscope, spend ~$100 on an old sony/tektronix 214 miniature storage scope.

http://www.teknetelectronics.com/Sea...&TEKTRONIX_214

Much easier to haul around and plenty of bandwidth for what you are trying to do.
They show up on ebay every now and then.

[brtech]

Originally Posted by the ancient one

If you want to play:

Before you spend $15,000 on a new oscilloscope, spend ~$100 on an old sony/tektronix 214 miniature storage scope.

http://www.teknetelectronics.com/Sea...&TEKTRONIX_214

Much easier to haul around and plenty of bandwidth for what you are trying to do.
They show up on ebay every now and then.

These are really cool devices. Any storage scope is cool, but these were really cool because they were so small and portable. It's just the ticket for looking at how the foil tip bounces when it hits.

[the ancient one]

Originally Posted by brtech

These are really cool devices. Any storage scope is cool, but these were really cool because they were so small and portable. It's just the ticket for looking at how the foil tip bounces when it hits.

Yeah... and because they run on batteries they can float and see things that happen on long wires that a grounded (line powered) scope can't see. I'd have one still if I could think of an excuse...

[brtech]

Originally Posted by SJCFU#2

My current test box has four meters (one for each line plus one for lame testing) plus LED's to indicate shorts between A and B or B and C lines. Two of the meters can also be used for weapons testing. I had originally toyed with the idea of adding another two or three meters to measure resistance between lines (perhaps on a 1K scale, whereas the other meters all measure single ohms). I abandoned that idea when the whole thing started to grow to the size of a briefcase. I'm currently working on a replacement for my current box - ideally something more lightweight and compact (I figure that I'm already carrying enough tools - I don't need another case the size of a small toolbox just for meters).

You ought to think about the digital one Ted has (actually, Al Dunbar built it). Basically, it's a string of voltage comparators fed off a resister ladder. You inject a current source into the circuit and light a string of LEDs corresponding to the voltage. I think it's 1 ohm steps up to 5, and then 3 steps of 5 ohms or something like that. You could battery power it, but Ted's has a wall wart supply and 3 capacitive coupled secondaries; not very efficient but they don't have to be. Separate LEDS for the shorts test. Ted's is not all that small, but you clearly could make it very compact.

This probably is the best design for the smallest high quality tester you could get. It's also extremely rugged.

Now, TournaTest is small, but not as small as you could make the digital one:

It's as small as I could make it with this size meter. It's the width of the meters pretty much smashed side by side, it's as wide as the meter plus enough room to make the connectors easy to get to, and it's as high as it takes to get the meter and a D cell to fit.

[KD5MDK]

The OP sounded so much like a Dan Box to me I was surprised he hasn't seen one.

[twisterfencing]

I can fix that.

Below is a link to a pic of the Universal Box made by Dan DeChaine.

http://i187.photobucket.com/albums/x...g/DSCN0219.jpg

This is the only box I use at meets. When I have to just do repair work, or work a table for weapon control, this box is with me. For those that are going to bring up the price on this thing, yes, its expensive, yet worth every penny. Dan makes every one of these by hand with the highest quality materials and workmenship. They Rock!

If your looking for a box to last you a life-time, this is it. If your are in your 2nd to 4th box that you are wanting to make, maybe not. Know this, I make test boxes for sale on a retail basis and I use them, but,,,,my Universal box is always with me due to the fact that mine will not do what Dan's will.

Hope this helps,


Gary Spruill

Originally Posted by KD5MDK

The OP sounded so much like a Dan Box to me I was surprised he hasn't seen one.

[LordShout]

I'm actually laughing out loud at myself for not realizing that someone would have already thought to do this, I like those boxes the only improvement I can see offhand would be miniturizing them.

Why 3 weapons at once? Well basically I just like to leave one perfectly working weapon hooked up to compare results to, if I need to reproduce a fault I can always do so on the working weapon and thus make myself sure of the problem before stripping wires and the like.

[twisterfencing]

Lordshout:

The only way to make these boxes smaller is to build a circuit board for them and use a diffrent current set up. I priced this out one time and shut it down once they went past $20,000 from a company in China. The main reason they are the size that they are is due to the meter sizes. They are not small ones. As you can see from my pic, they even light up. If you want/need, will take pics of the inside and you will see that there is not much room left inside.

Gary Spruill

Originally Posted by LordShout

I'm actually laughing out loud at myself for not realizing that someone would have already thought to do this, I like those boxes the only improvement I can see offhand would be miniturizing them.

Why 3 weapons at once? Well basically I just like to leave one perfectly working weapon hooked up to compare results to, if I need to reproduce a fault I can always do so on the working weapon and thus make myself sure of the problem before stripping wires and the like.

[LordShout]

I believe you the inside is crowded, if one was looking to make one small box you could probably do it fairly cheaply. The basic process for making boards can be done for fairly cheap at home, not as accurate and very labor intensive yet it can be done.

Forgive me if (as it seems you already probably do) you know this method.

Draw out the board circuit path you want with a 1:1 scale on either a computer of carefully by hand on paper, take a thin sheet of copper (or if you're cheap and don't mind a crap product alumninum foil (great for educational purposes)) and with a very thin layer of glue attach the paper to the copper sheet. Cut out your design, glue/laminate to the board of your choice and volia! Circuit board.

I could find in under five minutes a 1mm thick copper foil roll online so one could order that, 30 dollars for a 6 inch by five foot roll, enough copper sheeting for quite a ton of boxes with an intelligent design.

[KD5MDK]

I find it hard to believe that could reliably produce a smaller product than hand wiring.

[brtech]

It probably can't. A Dan box is determined by the box, which is a commercially available box from Hammond or Bud (don't remember which one, but I've seen it in the catalogs). The width of the 3 meters determines the width of the box.
The depth is determined by the meters, plus the space for the connectors. You don't want to push the connectors too far towards the meters, or you can't get your hands in easily, and the point of a three meter box is speed.

The height of the TournaTest is determined by the combination of the D-cell battery in it's holder plus the meter face it lies under. There is more room under the meter than under the connectors. I could have used a C cell, and gotten it slimmer.

The Universal (Dan's big 3 meter box with all the bells and whistles) is quite a bit higher than a TournaTest, but that is the size of the box. If you look inside a Dan box, he uses a lot of terminal strips. It's pretty clear you could take a couple of inches of height off of it, if you had the box custom made.

A circuit board isn't going to help. In each leg, you have:
The socket(s)
The meter
The battery
A pot for zero adjust
a resistor to set the scale

In TournaTest, I actually have a voltage divider, so I have another resistor, and that one, plus the scale set resistor are actually 10 turn pots. With that little circuitry, you don't get anything with a circuit board. Now, the Universal has waaay more parts in it, but it's still not that many underneath the cover.

LordShout was talking about DC-DC converters, and that would be best with a circuit board.

A circuit board WOULD make it much easier to build. That is a very good reason for creating a circuit board, but the hand crafted ones using copper foil aren't easier than hard wiring. Production PCBs aren't very expensive any more, but you still want to make 10 or so to make the project worth while. I'd like to do that some day with the TournaTest design, but so far, demand doesn't seem worth the effort required.

I will repeat that doing the digital design could get you a very small box. Maybe an inch deeper than the connectors. Best as a circuit board. Also a nice project I'd like to get to some day.

[twisterfencing]

Dan's boxes are LMB
http://www.lmbheeger.com/

I think, he uses the crown royal series with LMB.

Gary Spruill

[brtech]

I think you are right about LMB, but. I think it's the Uni-Cab series (UNC 4-6-10).

http://rocky.digikey.com/WebLib/LMB%...C%204-6-10.jpg

[fatfencer]

These are some awesome testboxes guys. I have to admit the ingenuity behind them is amazing.

I remember Dan telling me a story once about how one of his main boxes got all cut up by TSA as they were trying to figure out what the thing was. If i remember right he got the box up and running again at the same tournament.

Amazing. Simply amazing.

If I wanted something like this with the 3 analog meters and with all the widgets...could anyone provide me with directions?

The reason I ask is that although we have an excellent armorer here in AZ, she is in Tucson and is, methinks, overused. Dolly D.'s by far the best armorer we've got but we should have more people volunteering their time than just her for tournaments and such. People in this division often forget that there is a lot of community volunteering going on that makes tournaments happen. that's what so cool about Dolly. She takes initiative.

But she lives in Tucson and can't always make it to tourneys, though she usuallly does.

At my club right now I'm making do with an old Favero tester/fencing flick box to test weapons for people. Clearly not good enough.

I've always wanted to build something like this but haven't the faintest idea how to start.

My biggest problems is that I cannot read schematics.

Is there anyone out there that has build a test box like these we see in this thread that can do a step by step set of instructions. Mainly for the electrical connections and such.. you know, an Idiot's Guide to building test boxes?

Or if someone has a REALLY clean layout of the underside of one of these things and can take a REALLY clear photo that would certainly help.

People should really post this stuff here. I know I would, if I knew how to do it. This is the kind of stuff everyone can benefit from.

Thanks,

Fatfencer

[brtech]

I think people starting out with building their first box should build a single meter rotary switch box. I think you learn a lot from doing that. I posted complete instructions for doing that:
Instructions to build a testing box

However, it's a fact that a 3 meter box with purchased multimeters is the least effort test box, because all you do is mount the sockets, make 6 nice wires about 6-8" long with banana plugs on the end, 3 red, 3 black, feed them through holes in the back of the box, and wire:
Black A to reel end 3 pin A and a post for a mask clip
Black B to reel end 3 pin B
Black C to reel end 3 pin C
Red A to weapon end 3 pin A and a post for the clip
Red B to weapon end B (all the Bs, the B on the 3 pin epee, the B on the 2 pin foil and the B on the bayo)
Red C to weapon C (all the Cs as above).

You get 3 multimeters with Rx1 scales. Radioshack has them, or order them from:
http://www.multimeterwarehouse.com/analog.htm

Plug the wires into the meters, set them to Rx1 and start testing.

The problem with this tester is it doesn't detect shorts. Anyone can build one in a couple of hours though.

[Wink0192]

I used to work for GE Medical, where we made EKG test leads and cables. These had to be tested for resistance and shorts, just like body cords. Instead of using one meter for each line tested, we designed test sets that tested all the lines, and cross lines, in sequence. The circuit would check the ohms on each line and report any test that was out of range. It is easier to do today with a PIC microprocessor. Each line (A, B, and C) can be tested for the proper resistance range. Also, the lines can be checked for cross-shorts. With the microprocessor, this test can be done 10 times a second, or more. It would seem like each line is under continual test.

If there is interest, I can design the circuit and pre-program it into a chip. The chip can be used to build your own test unit, or I could make a PC board for the chip. Then all you have to do is build it into your own box. It would be more portable than a 3 analog meter box.

I am willing to do it, if there is enough intrest.

[DangerMouse]

I'd be quite interested.