DTS-1 Modifications

[johnnydmd]

As an owner of the now hard to find DTS-1 timing system, I've been pondering how to make it a little more useful. It has it's drawbacks. One, it's too small (short). Two, the controls are on the tree itself! Three, it has no displayed ET.

Well I broke out my trusty soldering iron, hadn't soldered electronics in 25 years. Threw it in the trash, and bought a Weller

My first order of business was moving the "set" button out of the unit and to a remote connected with a 20 ft cable. A phone cable worked perfect, right gauge and wire count. This will at least make it so that the tree operator doesn't have to walk up between the racers and press the stupid button.

It's pretty crude, the button is hot glued to the wood, and wires clamped with a bit of poly to keep them from getting yanked (glued the wires to the board at the other end as well to also prevent yanking/breaking).

Next up I will add a timer. I found this little guy that should work perfect https://quasarelectronics.co.uk/Item/3148t2-4-digit-stopwatch-timer-board-with-pause

I will have to check some stuff to see what signals are getting sent out from the lasers and lights. My initial thought is it would be easy enough to use the lights to signal the ET of the winner if using the green to trigger the start, and the "winner" lights to trigger the timer pause(any of the yellow lights will work since those start flashing immediately for the winner, and there's no issue with the yellow lights sending pause signals before the timer has started). Have to use the pause rather than stop because if it's flashing and sending repeated stop signals, that toggles the timer precision. That of course is going to include the reaction times. I don't know yet if there's a way to have a timer in each lane since nothing lights up in the loser lane, and the trap beam signal is coming in through radio signal, I'll have to look at the circuit board again to see if there's anything to tap in to there, but I suspect not. It may be possible to start the timer using the staging beams, but I am pretty sure the signal is sent when the beam is broken, rather than not. I'll test with my multimeter to see what's what on that end. If that can work, then it'll be a little closer to the real time, though I think still slightly off because the beam is probably not going to pass until the car is fully past it.

The reset timer can be done with the current set button, or add another button on my little wood panel if that is better.

Once I get the timer working, I might build a new light pole and move the lights from the circuit board, but that's a pretty big task.

 

[WickedFog]

I still can't believe one of the big manufacturers hasn't released a starting system yet worthy of the level the no prep cars are at now. Will be looking forward to seeing how this turns out.

On that note: how about everyone who reads this... go to Horizon and Traxxas and demand they come out with a starting tree that doesn't look like a Walmart toy.

 

[johnnydmd]

Well I bought a bunch of PVC, and the timer came in, it's supposed to snow like hell this weekend, so I'll be fooling around with this. I did test the timer and was able to start/stop it with a low level signal, so I think this is going to work

Ordering some colored bulb covers today. Going to design some sockets for the bulbs, and I actually think I'll be able to pull this off.

 

[WickedFog]

Can't wait to see what you come up with.

 

[Doom!]

Can't wait to see what you come up with.

I don't know, @johnnydmd is known for his lazy half ass efforts, just look at his Nitro's as an example.

 

[WickedFog]

Yeah, I know what you mean. Such a lackadaisical approach to every project, it just gets so hard to watch with any sort of anticipation for what's to come

 

[johnnydmd]

If I only put as much effort into yard and housework as RC's

 

[Doom!]

If I only put as much effort into yard and housework as RC's

Ain't that the truth! Guilty of that here too. Of course if my yard had a crawler course I'd be more focused on taking care of the yard.

 

[WickedFog]

Ain't that the truth! Guilty of that here too. Of course if my yard had a crawler course I'd be more focused on taking care of the yard.

I always assumed you lived in a cemetery with all the skeletons hanging around

 

[Doom!]

I always assumed you lived in a cemetery with all the skeletons hanging around

Well almost, we just skip the bury 'em part!

 

[johnnydmd]

Well, kind of at the point of no return I started desoldering a few of the existing LEDs. These are getting replace by much larger 10mm models that are diffuse types, very bright. I was able to test them and verify that they will work just fine. I designed my bulb sockets - and there's no need for covers, since these bulbs are plenty big enough. These sockets I'll need to print out this week.

I also ordered a bunch of low level trigger relays. This is necessary to make this timer work. Which, is gonna be tricky. The timer has a stop, start, and reset function. The timer will start when the tree is "set" - giving the racers a visual time cue to get staged. I can use the pre-stage sensor signal that is sent when it's broken to reset the timer - as it sends out a 5v signal when broken. It will be held in a perpetual stage of reset (in theory), until the beam is no longer broken. The stage sensor will send a 5v signal when it's broken which will now open it's relay, which will use the "normally closed" output. This means that the timer will then start after the sensor stops sending 5v, which is when it's no longer broken.

The DTS-1 flashes all of the lights in the winners lane when the trap lights are broken. I could use any of these (I'll actually have extra sockets because the DTS-1 has 3 stage lights on each side and I'm only using 2 for my tree), to stop the timer. It'll get a number of stop signals sent as it flashes, but that's ok - it toggles the display, but I think it's an odd number, so it should stop on the time. If not, I'll add another button on the operator controller to do that last one to get the time to show.

My only thought is this: There is most definitely a delay from the time the trap beams are tripped to when the tree lights come on - due to it using a radio. I'm wondering if running 132 ft wires might be the faster, more accurate solution? I'm sure there's a slight delay either way?

 

[johnnydmd]

More thought - I think the wired solution is best in that it'll be more accurate, as well as work for displaying the times of both lanes. This simplifies things a little too, other than I'll need a 130 ft cable, and a series of protectors covering it serving as a center barrier of sorts. Probably some lowly tented lexan, given I have mass quantities of extra strips laying around, or maybe a long rubber hose.

I printed out the light sockets. There are 3 types - the stage which has a four bulb piece, the countdown lights which are single, and the green/red which is a double. Here is the single (yeah, that's a green bulb I had handy just to see how it fit).

These get inserted into 1" ID PVC.

I then started replicating the laser trigger mounts, as well as a tree mount and the other end. These all get bolted down to a 1/4 inch piece of plywood, and then clear poly panels attach on the sides and top.

This will allow me to reshuffle how the internals are laid out so that I can fit the main PCB inside as well as the antennae PCB.

The lasers will get mounted in that center piece.

The tree slides over that 1" pole, and gets bolted in. I will add some metal weights on the bottom to keep it upright.

 

[johnnydmd]

Got some wiring started last night. Gotta pick up some hot melt glue to insulate the light tips and seat them, will do that this evening.

The toughest one of course are the stage lights, getting all that wire stuffed in there.

Just a little preview of what it should look like when glued up -

Next, I'll start cutting the pieces for the tree and assembling it.

Apparently I'm not the only one with the idea of "de-toyifying" the DTS-1. There's another guy that bought a full sized tree that is doing something similar. In his case he's going to have to use relays since his tree is running on a much larger power source (I think AC, actually).

 

[WickedFog]

I'm just going to sell a Kidney and buy the one Jegs sells. But that is looking great man!

 

[johnnydmd]

I got one side of the tree lights printed out, wired, and glued up. I ran out of time to start cutting the tree, but I hope to do that tonight.

Rough layout of the tree -

Thinking about it as I post this, I'll probably make the tree a little bit shorter, and the base a bit longer since I want to keep it one unit similar to the original DTS-1. That way people are in the right line of sight when lining up and launching. So about what is laid out in the picture would be what's sticking out of the base (there was about an extra 10 inches cut off the pic at the bottom). This would be about 30 inches in height overall.

[EDIT] - it just occurred to me that the DTS-1 is really built backwards! I need the tree to be on the other end of the base, so that'll mean flipping some things around, etc - but no problem.

 

[johnnydmd]

Got the pieces cut, and one side wired. I still need to cut the base post in half and use that remaining cross piece to route the wires out of the tree. My hacksawing skills weren't perfect, I think I have a pipe cutter in my shed that I can straighten out the ends of some of those a bit. I'm gonna shorten the sections that connect to the lights about a half inch on each side.

Once it's all lined up and fully together, I'll put some set screws in to keep it lined up right, but it's pretty tight as is, have to use channel locks to adjust anything.

Gonna print out the base parts tonight. I think I might have the base and tree finished by the weekend. Then it'll be on to working on the timers.

 

[johnnydmd]

I spent a lot of time on it this weekend, and got the base going. Not pictured, but the lights are finished. Still printing out some of the base parts. The piece that holds the lasers finished this morning, I quickly tested fitment before work - it was good with a little modding to create clearance at one spot.

I got the main PCB and antenna mounted. I'm also printing out a piece that holds those two aluminum blocks and has legs coming out of the side for added stability.

I spent much of yesterday de-soldering existing LED's. Got one side done, and the holes cleared. Tested to make sure they all still worked. That's the least fun part of all of this, lol.

Not pictured, but I got the tree lined up, straight, and drilled holes and screwed it all together.

This project is harder and taking more time than building the dang cars, lol.

I designed another piece that will hold the weight bars and stabilize:

 

[Doom!]

This project is harder and taking more time than building the dang cars, lol.

But your going to have the coolest Christmas Tree on the block!

 

[johnnydmd]

Everything is printed out, and I've got the layout completed. Need to bolt up the lasers, etc, and then solder all the light wiring to the main PCB, and it'll be functional.

The stability brace will have "pads" of the same wood as the base, this was to avoid the possibility of the plastic getting soft on hot blacktop. A second, wooden brace will mount on the front by the tree (also serves as an anchor for the bolts going through the tree tube holding it to the base). After it's all tested, I'll cut the .060 poly panels that cover everything up. There's also a black printed piece that bolts over the laser apertures to shield that assembly from the sun. I'm aware of the missing screws on the tree itself, I had to go to bed before I finished them, it was late

 

[johnnydmd]

Made a ton of progress, and got the base finished. Got started on the lane timers too, and got it working!

The biggest fun was all the de-soldering and soldering of the new lights.

Then I finished up the base, and tested. Everything worked as before.

Then I took the top off, and got busy trying to figure out the lasers and the relays and timer. It wound up being even simpler than I planned.

After I got the first lane timer working, I put in an order for a second. (Didn't want to waste any more cash if I couldn't make it work).

It's actually pretty simple once I got the hang of the relays and what they required. It uses two relays per lane timer. The first one is hooked to the stage laser, and goes to the timer reset. The second is hooked to the first laser in the speed trap, and goes to the timer stop. The timer start is jumped, so that when you trigger a reset, it begins timing.

So it works like this:

When the operator presses the system set button, the lane timers then begin counting - giving the drivers a handy indicator to get to the stage before the 25 seconds allotted is up. (this is really just a convenient, unplanned but useful side effect). When a driver reaches stage, the timer goes into reset mode, and goes blank. Also a good side effect, to prevent any eye distractions from LED's. When they leave, the circuit goes back open, and the timer starts counting. Then when they cross the first trap laser, the timer stops. Simple really.

To keep this accurate, I am running a 130 foot cable between the tree and the trap that connects the lasers to the relays for the stop function. It'll use protectors to keep it flat so cars car run over it in cases of crossing lanes.

I'm going to upload all of the STL files and write up a more comprehensive guide next week, in case anyone else is crazy enough to try this. I think the effort was well worth it, but man I see now why a Trackmate system is 3k.