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Blackranger3d
2006.02.15, 11:04 AM
Purpose: To build a cheap (relative to the $600 counters people are using) reliable lap timer / counter.

Application: My race track in my basement.

Option 1 – Wired to Keyboard
Option 2 – Wired direct to LPT port
Option 3 – Use 4 – 6 TOMY LAP COUNTER DIGITAL TIMER

Generic Apparatus:
- 6+ laser source (laser pointers)
- 6+ light detectors (phototransistors)
- PC Software to record laps and times (there are lots out there, this is not a problem)
- wood / plastic etc to build gantry
- flags for car antennas


Option 1.
Option Specific Apparatus
- keyboard
- PC


Method:
Wire phototransistors to a key board so that when their source of light is broken a keystroke is registered on the keyboard. The PC Race Software will then take this keystroke and record a lap. For most of the programs I have seen a keystroke from 1 - 10 will register a lap in the corresponding lanes (i.e. 1- 10). Each phototransistor will be wired in at increasing height along the gantry. Each car will have a flag on its antenna, the height of which corresponds to the sensor.

Pro
Will allow race to be recorded on laptop, with sound effects etc.
Lots of wiring (I like building this stuff)

Con
Lots of wiring (lots to go wrong)
Have to figure out how to trigger keyboard

Option 2
Option Specific Apparatus
- Keyboard
- PC
- DB25 plug

Same as above, except wire direct to PC though DB25 plug (LPT port).
Pro
Simple

Con
I cannot get it to work. I don’t have an LPT port on my desktop PC, and I have not been able to figure out how to turn the LPT on my laptop on. I assume the laptop port works since the laptop is about 2 months old.


Option 3
4 –6 x TOMY LAP COUNTER DIGITAL TIMER HO AND ALL SLOT+RC CARS (http://cgi.*******a/ws/eBayISAPI.dll?ViewItem&item=6033400108&rd=1&sspagename=STRK%3AMEWA%3AIT&rd=1 )

Take 6 of these brake them apart and then mount them in wood or plastic at every increasing height. Follow this tutorial (http://mini-zracer.com/forums/showthread.php?t=20805) to extend the range. Then put flags on the cars and race.

Pro
Simple.
Electronics already done.

Cons
Too easy.
Display too small, no cool sound effects. Cannot print out results.


My dream would be to use the core system. But good god almighty I am not paying $600USD + for it.

So I guess my main questions are.

What are you thoughts on the options?
How do I wire a phototransistor to trigger a keyboard keystroke?
Is there a way to wire direct to a keyboard port (I don’t have a joystick port on my desktop or my pc)?
How do I turn on my IBM R51 LPT port?
Any other suggests for counters?

I have posted this in a few forums to see if I can get some good advise.

Thanks for reading.

Spoon
2006.02.15, 11:30 AM
I think option 1 may be your best bet. The wiring would be pretty easy to test and debug. Once you got one working, the rest should be identical.

Without actually trying it, here are my thoughts.

1. You are going to need to dismantle a keyboard and see how the keys are actually triggered. I suspect it's some sort of electronic contact (i.e. a switch)

2. You are going to have to find an IC (integrated Circuit) that can be triggered by the voltage change (or resistance change) of the phototransistors.

3. You are going to have to figure out how to make that IC activate the appropirate switch on the keyboard. This is where you would wire directly into the keyboard. From there, the keyboard and computer could figure out which switch you depressed, you don't have to deal with that "translation".

I don't know off hand the characteristics of a phototransistor. I am sure you can find a datasheet or do a simple test. I think it's actually a voltage change...some google searching should reveal some answers.

It sounds like a fun project. If I come up with any ideas or find anything specific, I'll let you know.


One more thought...can you buy an LPT card for your desktop? I think I have seen timing systems that are wired to an LPT port. If you can get a card, that may be easier than trying to hack a keyboard and make a control circuit.

Blackranger3d
2006.02.15, 11:48 AM
Thanks, this is the best advice I have seen so far.

I don't really want to involve my desktop since it is in my office which is now where near my track.

I am hoping to connect the lap counter to my Laptop throught either the LPT port (can not get it to work so far) or through an external keyboard.

Blackranger3d
2006.02.15, 11:51 AM
I have found this, http://aticatac.altervista.org/schemi/chrome_keyboard.pdf I don't fully understand it.

But my first thought is that I can build a circut board to just out put keystrokes 1 - 10.

I then still have to figure out how to get the transistors to activate the keystrokes.

rmfroyd
2006.02.15, 11:58 AM
I just built a laptimer using the following program

:http://www.gregorybraun.com/LapTimer.html

I used 4 lasers and a printer cable to hook up to a laptop. If you look around the sight it will show you how to wire your ir recievers to a printer cable so you can hook it up to your computer.

It works very well, however you need bright lasers. I searched the internet and many people recommend the cheap keychain lasers that you can buy at dollar stores. These did not work for me. I ended up have to puchase lasers that are used for laser sights for guns from Walmart.($20 each) Once I installed those it works real well. If you have any questions let me know.

Spoon
2006.02.15, 12:37 PM
I have found this, http://aticatac.altervista.org/schemi/chrome_keyboard.pdf I don't fully understand it.

But my first thought is that I can build a circut board to just out put keystrokes 1 - 10.

I then still have to figure out how to get the transistors to activate the keystrokes.

Could you attach the pdf, I can't get to the link.

The problem with outputting the keystrokes without the keyboard, is that you don't know what a "1" looks like to the computer. It's a possibbility, but it's another bit of research required.

Spoon
2006.02.15, 03:14 PM
Nevermind I can get to the pdf.

The more I think about this the more I think it can be done.

First, the schematic. It's basically showing you which combination of control wires generates which keystroke. It's sort of like a telephone. For a basic keypad there are 3 columns and 4 rows. Each row and each column have a wire associated with them. When you press the number 1 current travels from the wire at row 1 to the column at row 1 so the phone knows what number you are pressing. I don't know exactly if it works that way, but that's the general idea.

That keyboard schematic is just showing you which control wires have to intersect to get that particular key.

So I think what you are going to need is some sort of transistor circuit. It's been a while since I have done any circuit design, so I can't give you specifics.

Do some transistor research. You will find that a transistor is basically a switch with three inputs. Actually one input, one output and one control.

For you timer you would connect the input and output of the transistor to the intersecting wires. For example, to control the "1" keystroke on that schematic, you connect A11 to one end of the transistor and A8 to the other. Your phototransistor would control the switch.

You will have to figure out the specifics to control the transistor but I am sure there are circuit diagrams out there.

Spoon
2006.02.15, 03:19 PM
http://www.hiviz.com/tools/triggers/makeown.htm

Check that out for a diagram that's similar to what you are trying to do. It triggers a buzzer when the light is broken.

rmfroyd
2006.02.15, 03:34 PM
Just my 2 cents worth. The lap counter I made that I mentioned before cost about $150, a large portion of that being the lasers. What you guys are proposing with the keyboard is cool and would be a fun project, but there are easier ways to go about doing it. Almost all lap counting program on the web usually have schematics for wiring inputs to your computer,(printer ports, joystick ports, etc), that aren't complicated and require basic soldering skills, most don't need transistors, or resistors. If you are doing it for fun go for it, but there are easier ways out there.

Blackranger3d
2006.02.15, 03:43 PM
Thanks rmfroyd. But in my first post I said this.

>>>>>
I cannot get it to work. I don’t have an port on my desktop PC, and I have [b]not been able to figure out how to turn the LPT on my laptop on. I assume the laptop port works since the laptop is about 2 months old."
>>>>>>
I want this counter to be usable on my laptop (which has LPT issues).

All the diagrams that I have seen are for LPT (does not work on my laptop) or joystick ports (don't have one on my laptop).

So I figured the best option would be a keyboard based solution.

Blackranger3d
2006.02.15, 03:55 PM
Spoon, thanks for the help you have set me in the right direction.

I have posted a question in a DIY electroinc forum. I love the internet, there isn't anything that you cannot learn if you try.

http://www.electro-tech-online.com/viewtopic.php?p=127105#127105

cdog4w
2006.02.15, 04:38 PM
Con
I cannot get it to work. I don’t have an LPT port on my desktop PC, and I have not been able to figure out how to turn the LPT on my laptop on. I assume the laptop port works since the laptop is about 2 months old.

I had the same issue, but I figured it out: the issue was that the parallel port was setup in mode "ECP" in the bios of the laptop's motherboard. So I jump into the bios and the settings are "Normal", "Bi-directional", "ECP" and disabled. Once I set to normal and rebooted, sensors worked fine.

Give it a shot, its very simple and works pretty well. The main issue is the quality of laser, I'm using the cheap laser pointers (4 for $9 shipped off ebay), but they dim after a few minutes. I might have to try the gun lasersight idea... at least for my primary counter. You can see my build thread here:
http://www.epoch1-43.com/forums/showthread.php?p=758#post758

Blackranger3d
2006.02.15, 04:43 PM
Thanks for the BIOS tip. I didn't even think about looking in there.


I'm using the cheap laser pointers (4 for $9 shipped off ebay), but they dim after a few minutes. I might have to try the gun lasersight idea...

Are you running off battery, or AC adaptor?

cdog4w
2006.02.15, 05:15 PM
Are you running off battery, or AC adaptor?

Tried both. Even my regulated PSU.

cdog4w
2006.02.16, 02:15 AM
Put my RCP back up (it hogs pretty much the entire living room when up, and in an apartment, thats hard to deal with for long), and finished adapting my lap timer. Works wonderfully. The dimming didn't seem to be an issue, I ran 2 50 lap trials w/o dropping a single lap powering the laser on 3AAA. Using lap timer 2000. I still need to fix up the rest of the lasers (you can see them dangling), but once thats done I can run up to 4 cars (with the current rig).

pic (http://img116.imageshack.us/img116/1807/laptimer12fp.jpg)

pic2 (http://img112.imageshack.us/img112/1016/laptimer09vy.jpg)

bluegrooveracer
2006.02.18, 05:52 PM
i have a problem related to this subject i have made a laser / photo transister
style lap counter as found here http://www.schumacher.clara.net/laptimer.htm
but my lap top only has usb ports so i wired the photo transisters to a 9 pin serial port
and connected that to a usb/serial port adaptor but i cant get it to count laps
i have tried the track mate and lap timer 2000 if any of you have tried this and had it work with a 9pin serial to usb please let me know how or what you did thanks for any help you could offer

rmfroyd
2006.02.19, 08:27 PM
This is the exact same page/project with laptimer 2000 that I did. However I did not have the usb/serial port adapter problem. The only thing I can tell you is double check the strength of your lasers. Test them in a completly dark room with holding your finger over the photo transistors. If it doesn't work then it is a problem with the usb adapter. Just this weekend I brought my laptimer out during the day and it didn't work at all. The sun was too bright and my photo transistors(radio shack) couldn't pick up the car breaking the laser beam. I had to use my finger held over the phototransistosr for it to work. I believe that the Radio shack transistors are overly sensitive. So do this as a quick check. If it still doesn't work you may be SOL, but I don't see why it wouldn't work.



i have a problem related to this subject i have made a laser / photo transister
style lap counter as found here http://www.schumacher.clara.net/laptimer.htm
but my lap top only has usb ports so i wired the photo transisters to a 9 pin serial port
and connected that to a usb/serial port adaptor but i cant get it to count laps
i have tried the track mate and lap timer 2000 if any of you have tried this and had it work with a 9pin serial to usb please let me know how or what you did thanks for any help you could offer

Spoon
2006.02.19, 10:54 PM
This is the exact same page/project with laptimer 2000 that I did. However I did not have the usb/serial port adapter problem. The only thing I can tell you is double check the strength of your lasers. Test them in a completly dark room with holding your finger over the photo transistors. If it doesn't work then it is a problem with the usb adapter. Just this weekend I brought my laptimer out during the day and it didn't work at all. The sun was too bright and my photo transistors(radio shack) couldn't pick up the car breaking the laser beam. I had to use my finger held over the phototransistosr for it to work. I believe that the Radio shack transistors are overly sensitive. So do this as a quick check. If it still doesn't work you may be SOL, but I don't see why it wouldn't work.

You may just need to shield the transistors for ambient light. The most recent mod I made to my lap timer inlcuded putting the transistor about halfway into a 4" aluminum tube. That way the only light that would really get picked up by the transistor was anything coming directly at it. If the transistor isn't shielded in some way or is in a really shallow tube, you will get a lot of light hitting it and blocking the laser won't register a lap.

Zlarrz
2006.03.03, 12:26 PM
Hello im building a lap counter system but how do you guys get the laser-module
out of the" laser-chassi"?
This system with lasermodules seems to work pretty good, cus im not wasting money on a lap-Z system + transponer :)

Blackranger3d
2006.03.03, 01:00 PM
Hello im building a lap counter system but how do you guys get the laser-module
out of the" laser-chassi"?
This system with lasermodules seems to work pretty good, cus im not wasting money on a lap-Z system + transponer :)

Why take it out. Just cut the back to expose the battery spring and then conect power to that.

Spoon
2006.03.03, 01:19 PM
Hello im building a lap counter system but how do you guys get the laser-module
out of the" laser-chassi"?
This system with lasermodules seems to work pretty good, cus im not wasting money on a lap-Z system + transponer :)

Yeah...DO NOT PULL THE LASER MODULE OUT OF THE CHASSIS. (sorry for yelling)

It seems that the power of the laser has a lot to do with the fact that it's enclosed in the little tube. I tried to cut mine down to make it fit in a box and I noticed the beam was not as powerful. I thought the batteries were wearing down but it was because I cut the tube down.

I had already ruined it so I figured why not keep experimenting. The shorter I made it, the worse it got. I ended up getting another laser.

I'll be posting pictures and updating my tutorial with the additional info.

Blackranger3d
2006.03.03, 01:22 PM
Yeah...DO NOT PULL THE LASER MODULE OUT OF THE CHASSIS. (sorry for yelling)

It seems that the power of the laser has a lot to do with the fact that it's enclosed in the little tube. I tried to cut mine down to make it fit in a box and I noticed the beam was not as powerful. I thought the batteries were wearing down but it was because I cut the tube down.

I had already ruined it so I figured why not keep experimenting. The shorter I made it, the worse it got. I ended up getting another laser.

I'll be posting pictures and updating my tutorial with the additional info.

Dang it does that mean the 99 cent lasers would work fine, if they are not cut down?

rmfroyd
2006.03.03, 01:45 PM
Dang it does that mean the 99 cent lasers would work fine, if they are not cut down?

While I was trying to figure out a laser solution to my lap counter, I tried the 99 cent lasers and only one worked(out of 10) that were cut down. I also tried using lasers(5 of them) that were not cut down and I couldn't get any of those to trip the lasers either. Quality control on a 99cent laser isn't the highest so you might get lucky on one or two but I went through 15 before I got one to work. Another point of interest. If you are going to power you lasers with an ac adapter, the cheaper lasers might not work as long. I read that the lasers in the cheaper units factor into the battery draining to supply the power. Therefore if you supply constant power the cheaper lasers might burn out quicker.

Taazz
2006.03.03, 01:53 PM
Dang it does that mean the 99 cent lasers would work fine, if they are not cut down?

We built a system using the 99 cent lasers and had nothing but problems. They would go dim for virtually no reason at all. It appeard to have something to do with power surges or just being used too long.

I finally built a new tower using laser levels that I got from RS during a day after Thanksgiving sale for $5 a piece. I used IC3 regargeable batteries (two AAA for each level, 6 levels total). We had no problems at all with counting, lasers burning out or going dim, or ambient light causing a problem.

The 99 cent lasers use inferior modules and just don't hold up to continuous use.

We did hook up to the Serial port. My son even wrote a VisualBasic program that simulated keystrokes when the laser was broken so we could the LapsFree timing software which only recognizes keystrokes or AMB inputs.

Zlarrz
2006.03.03, 04:11 PM
Thx guys, on some pictures i have been seen some one take out the little module out of the chassi but thx for telling me i just cut that much i need to solder the cables.

1 more qustion the power + and - ,one cable at the spring and the other in chassi? I am thinking about using a 4.5V Adapter as power supply.

Edit: Found the link:

http://www.itsallbutstraw.com/modules.php?set_albumName=album03&op=modload&name=gallery&file=index&include=view_album.php&page=1

Taazz
2006.03.03, 08:42 PM
I hope you have better luck than we did using the cheap battery operated lasers. We tried it with the 4.5 adapter and had nothing but problems. If one would come disconected or get turned off the others would get a power surge and they would all go dim and become useless. We also tried it using three rechargeable batteries (3.6 volts) had had the same problems.

You need a high quality laser to hold up to continuous use. You can use the cheap lasers, but you will be replacing them on a regular basis. We found it was less expensive in the long run and much less frustrating to use the laser levels that we finally ended up with.

cdog4w
2006.03.03, 08:53 PM
I had no trouble with mine after cutting, and they are the 99 cent lasers. The dimming is an issue, but it hasn't affected my lap counting. Be careful of the "lens" part, since that affects the focus of the beam etc. Check the "new laser soldering" attachment here to see how I did it. I direct soldered to the laser diode circuit, not to the springs or anything like that.

http://epoch1-43.com/forums/showpost.php?p=314&postcount=4

cdog4w
2006.03.03, 09:14 PM
Taazz: Is this (http://www.radioshack.com/product/index.jsp?productId=2123518&cp=&pg=1&y=10&kw=laser&x=10&s=A-StorePrice-RSK&parentPage=search) the RS level you're using? If not, is this (http://www.radioshack.com/product/index.jsp?productId=2118093&cp=&pg=1&y=10&kw=laser&x=10&s=A-StorePrice-RSK&parentPage=search) it?

Looked at home depot online, but they didn't have anything cheaper.

Taazz
2006.03.03, 09:50 PM
Here is a link to the type of level I am using. Not a bad price either

16 inch laser level (http://www.toolprice.com/product/2929G)

This price is for a case of 5. They also sell them for 6.99 each.

I made a frame out of aluminum with threaded rod running horizontally to support the front of the level and drilled a hole through the back of the level (this one looks like it already has a hole where I drilled one) and used nuts threaded onto a vertical rod to support the back. They ended up stacked 6 high laying on their side. Works great and is completly adjustable.

I will try to post a picture of my system. Have to dig it out of the garage as it hasn't been used for a bit.

Blackranger3d
2006.03.04, 01:19 AM
Maybe you guys are having bad luck, I just ran two $1 laser for 6 hours straight with no dimming. I just made sure not to cut it.

To conect to the spring I use an aligator clip and stick it in.

cdog4w
2006.03.06, 06:28 PM
I haven't run mine that long, but I have done 20 min w/o trouble. If it dims, it still doesn't drop laps...

If I start having trouble, now I know a good replacement, thanks Taazz.

wwwes
2006.03.20, 11:48 AM
Have you had any problems with your cars glitching. We have the lap 200 software running with four cars on the track. When My car on channel one passes under the gantry it makes the car turn hard left. When you turn off the lasers the glitch goes away and the car runs perfectly. Any help would be greatly appreciated.

cdog4w
2006.03.24, 07:47 PM
Have you had any problems with your cars glitching. We have the lap 200 software running with four cars on the track. When My car on channel one passes under the gantry it makes the car turn hard left. When you turn off the lasers the glitch goes away and the car runs perfectly. Any help would be greatly appreciated.

No, but I've only run 1 car at a time so far. Doesn't make much sense tho, unless the laser emits RF in the 27MHz range which I doubt. What kind of gantry is it? If its metal it can have RF reflective properties and could be the culprit.

pianoman
2006.03.27, 01:17 PM
Have you had any problems with your cars glitching. We have the lap 200 software running with four cars on the track. When My car on channel one passes under the gantry it makes the car turn hard left. When you turn off the lasers the glitch goes away and the car runs perfectly. Any help would be greatly appreciated.
Place the gantry over a left hander in the track. :)

wwwes
2006.03.31, 02:52 PM
Place the gantry over a left hander in the track. :)
the gantry is amde of wood and yes it is placed in a left hander