[Phil Kalbfell]

I had a similar problem,using a PCI Parallel card for my Alps Printer.
Never solved the problem, I believe is was a Bios problem.The pc would see the port but could not re configure it.

 

[Savage]

Many thanks for your input gents.

Leo and Phil, I have come to the conclusion that it must be an issue with the adaptor and/or software incompatibility.

I have now ordered an Arduino uno clone. As RC has an interface for that hopefully this will get things working !

 

[scuderia_turini]

Yes Arduino is a safer bet. I tried the Doug Brown port tester and it worked on my R-C machine (LPT1 built in) but the notes for the InpOut32.dll file say that that will not work with PCI boards. So it looks like the parallel type boards are as tricky as the USB adapters that are notorious.

Lots of people using Arduino interface now so should be relatively straightforward.

Leo

 

[Savage]

Man, this is doing my head in :angry:

Arduino got, set up and working, but the sensors wont work if they are much more than 3cm apart, not much use for a Lightbridge 9cm above track !

I even swapped the RX and TX units over for some I found that were spares from my last track, and same results.

I don't know if the USB is not providing enough juice (checked and multi-meter says they are getting between 1.1 and 1.2v and 41.9 ma.

I have even taken the coloured led out to try, no difference.

 

[Phil Kalbfell]

IMO your sensors seem o be the problem.
.Most sensors will work using any light source, so can be tested using a tour he or lamp.
This way you can see if your sensors will work With a stronger light source further away.
I had this problem with the original sensors that used to come with Trakmate, that is why I started to test sensors from other source.
You could also power the transmitters from a power pack or similar.

 

[Savage]

These ore the receivers I got, along with matching emmiters from the same seller:

https://www.ebay.co.uk/itm/10-x-5mm-LED-Infrared-Receiver-940nm-IR-LED-Diodes-IR/232339287646?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

 

[Phil Kalbfell]

They are Photo diodes, I have never managed to get them to work with any reliability, I always use Photo transistors.

Also 3mm diameter is easier to instal in the track..

 

[Savage]

Hi Phil,

TBH size is only a mater of drilling the appropriate hole

I went for 5mm thinking they would have a better spread for receiving TBH.

Last time around I used the old Maplins YY66, (ithat is 3mm but no idea if transistor or diode) they worked flawlessly for the 5 years the track was running.

I did try one of those I found in my box of bits, but it didn't improve the range much.

Would something like this be what you are referring to ?: https://uk.rs-online.com/web/p/phototransistors/9128514/

And were can i get just a few I dont need 2000

 

[scuderia_turini]

Hello Savage,

Have you tried a torch or filament bulb as the light source?

Alternatively can you shorten the gap between the emitters and receivers?

Leo

 

[Savage]

Tried an LED torch but it wont register at all.

At 3 cm I can't shorten it or I could only run bare chassis

 

[RichD]

At first I thought that your problem was that the emitters and sensors were not matched, but you say that they are. You should try the suggestion that you move the emitters and sensors close together, if that works you might need to have two or three clustered emitters for each sensor when they are further apart.

 

[scuderia_turini]

Hello Savage,

Difficult to know what is going wrong, as you have experienced previously, this should be reasonably easy. I have rigged up a test set and put a video on YouTube which will hopefully be fully uploaded by the time you see this.

I used a 5 volt power supply for the emitter and with a 510 ohm dropper resistor (that's what I use for 12volts). The LED still gave enough IR light to trigger the photo-diode from 15cm away. Normally I just wire the diode directly to the Parallel Port or Arduino port so ignore the resistor in the demo, that is just there to show that the diode is switching on and off. These are virtually random I-R units, bought separately via Ebay so not especially matched.

Apologies for the unscripted twittering in the video, I meant to point out that the diode is wired with the Positive/Anode long lead to the negative side. I will happily send you the photo-diode and LED test rig if you send me a message with your address. Could stick in the post later today (24-Dec-2018) but the Festive shutdown is looming.

Video should be here :-

(Still over an hour of upload to go).

Leo

 

[Savage]

I meant to point out that the diode is wired with the Positive/Anode long lead to the negative side.go).

Leo

Hi Leo,

Many thanks for your help, the key was right there.

Being inexperienced in electronics, I assumed all leds type components were supposed to be wired short to ground or -ve.

The sensors it appears, not so. Wired as you said long lead to ground on the arduino and they are working at well over twice the distance needed for the light bridge, I feel like a right plonker !

Many thanks to all you guys for you help, have a beer and a mince pie on me

 

[scuderia_turini]

Brill !

Enjoy Christmas, hope Santa is good to you.

Leo

 

[RichD]

As far as I know the long leg of a LED always goes to ground (-).

I'm glad that you got things working, enjoy the holidays!

 

[Savage]

The coloured leds I bought state long is positive, as does startingelectonics.org so I don't know, but its working now so that's the main thing

 

[RichD]

Oops! I just examined my LED collection, some of those have equal length legs, some have longer positive legs and some have longer negative legs. I have had some of those LEDs for many years, perhaps that was not standardized at one time. For through panel LEDs there is a flat spot that indicates the negative lead. My experience has been that if the voltage is correct and you hook up the LED backwards it will not light, but it will not be damaged. I imagine that if a person that was not experienced with using LEDs hooked up backwards he might be tempted to increase the voltage and that would be likely to burn it out.

 

[scuderia_turini]

Yes, the convention for LEDs is that the Positive/Anode lead is the longer one. Also, and perhaps originally, the Negative/Cathoide lead is adjacent to a flat section of the flange at the base of the LED (so if both same length that would indicate the polarity).

Leo

 

[slotcrazy]

Savage - did you solve your problem ?

One thing I didn't add at the time, as I didn't ant to further complicate the issue - but will now as it may yet help.

LEDs described as Infra-red, come in two wave lengths - pure IR, which is 940nm wavelength, and 850nm - let's call them the 'fatherless'

version. I always prefer to use the 'fatherless' version, as these also respond to much of the visible light spectrum, whereas pure 940nm ones do not.
I also find that the 850nm ones are generally more sensitive. Check out this EBAY listing for 940 and 850nm LEDs.

Check every time you hookup that the LEDs that they are lighting. In my experience, hooking them up the wrong way around at correct voltage DOES sometimes blow them up. The only time I have had to repair my light bridges is a couple of guys who hooked them up the opposite way around when they couldn't see white light, and cooked one or two of the bank - requiring me to replace those, and send them a second instruction sheet about looking at them through a digital camera or phone, not with naked eye (although the 850nms conveniently glow a pretty pink to the eye if you look directly up their spout.)

There seems to be a dearth of 850nm 3mm diameter photo transistors on EBAY at present. No idea why. I usually buy 10 packs from a multitude of offerers. There are some stupidly expensive UK sources, making about a 50,000% markup......

 

[Savage]

Hi Slotcrazy, Yes, see post #33 above

Before that I had ordered various others as they are low cost, including some phototransister sensors rather than diiodes. Now surplus to requirements as the originals work fine. I am swimming in them now !

I had used 940nm on my previous track and had no issues in the 3 years it was up, so I went for that wavelength again.