How to Build a Tuned Infrared (IR) Detector Circuit

The article is a continuation of the prior publish where we wanted to come across an alternative for developing special infrared IDs for trains in a model locomotive system. The following we seek to figure out the application in detail and discover how it could be possible to efficiently put into practice the thought making use of tuned IR detector circuits.
The reason why don’t you inhabit Ribe, Denmark or me in India. Helps make it all more convenient:o)
Due to the fact we have not less than 50 locomotives and more will be I am sure. The thought of developing 50 units on each train station track won’t work, but possibly you can easily lower the level of circuits on each track by permitting only a few trains pass on eg. track 1 and some on track 2 and so.
The suitable answer may be to are fully aware of where every locomotive could possibly be on the tracks. A few modules from the big companies apply RF or the digital signal by way of the tracks to show the position of the trains. The only bad thing about their modules is the price.
A lot of people have a small track with a number of locomotives allowing it to conveniently run the model trains manually. Ours is too big and supervising 50 trains is not human possible. Because of this we now have produced a software to serve us. The software though needs some inputs to work as I mentioned prior. All the inputs to the software derives from S88 modules (special produced to model train track by some German company), USB and parallel I/O circuit boards. This provides me to another point where you most likely would have an idea.
I have created a small circuit to turn on/off transistors to switch a relay or something. Are you experiencing an idea to a homemade USB circuit with input / outputs? I desire a lot of input /outputs for our computers.
Now to the way the trains stop, slow down and accelerate. All trains are complete with a digital controller and by way of the track acquire tips to quicken, stop, turn on lights etc. Our software delivers these orders by way of a digital controller unit from Märklin (Märklin 60212) hooked up via LAN.
These kind of information is to merely show you exactly how things works for the model trains.
So to stop a train I would probably send out a command from any computer in our house or manually by locating the ID of the train and advise it to stop from the 60212 command unit.
The RX module is the receiver right? If yes certainly they needs to be under the tracks and the TX module in the train. The RX module should on approach of a train switch an S88, port on the USB or parallel interface board to ground. My software watches the S88, USB and parallel interface boards and act on a switched port to ground. I hope you can fully understand my description. So if your circuit could tell the computer a specific train has parsed. The computer could send the commands.
Band pass filter is possibly a remedy. The computer though wouldn’t be familiar with which train to stop or am I acquiring this wrong? But the band pass filter would come in useful more places in model train tracks. Eg. to switch crossovers and many much more.
It is my opinion 8-10 predetermined trains are sufficient.
I do think I didn’t make clear myself correctly. The thing is that the interface circuit linked with the computer identifies when an input port is switched to ground. Most interface boards for computers do this as far as I am aware.
I have added a file with the schematics of an interface board from Velleman. This is exactly merely certainly an interface board.
That was what I ensured that switching to ground. Can this not be performed with a BC 547 NPN transistor on the output from your circuit?
Fundamentally it is simply to advise which train is approaching which station. How the information lists up in the computer I am confused which is usually best. The thought of wirelessly sounds good, but is it obtainable?
My choice in the first place was which includes a circuit which may advise the computer through an interface board which train is approaching which station.
You will discover however one big difficulty regarding making use of interface boards. How many boards necessary and how many could be hooked up to one PC.
If you take a look at the schematics of the Velleman K8055 you can find 2 analog inputs 0-5V perhaps these can possibly be applied.
A few circuit selections for the suggested detection may be noticed below, these kinds of could possibly be experimented with:




Both the circuits can be employed for any application that will require a specifically tuned infrared detection for instance in IR remote control, IR security systems or IR based lock and key devices.
The first circuit takes advantage of a LM567 step locked loop frequency detector chip to form the receiver circuit.
R2/R3/C2 fix the latching frequency for the IC such that the circuit reacts and generates a zero logic output on detection of this frequency at its input pin3 via the photodiode.
The photdiode is brought on by a 555 based astable circuit revealed at the left of the diagrams. The 555 circuit furthermore utilizes a photo diode for transferring the frequency over the acquiring LM567 photo diode device.
The 555 transmitter needs to be tuned specifically to the frequency that may be set with R2/R3/C2 in the LM567 circuit. Anything else is just overlooked by the Rx circuit.
In the second tuned infrared detector circuit, an LC tuned opamp is commonly employed for obtaining an replying to the specifically tuned transmitter frequency.
The L1/C1 feedback loop located across the opamp output input pinouts determines the latching resonant frequency upon which it could be designed to latch on.
L1/C1 could be correctly refined for accomplishing some other different tuned frequencies for carrying out the locking actions.
Here too a 555 astable is employed as the IR transmitter for activating the opamp Rx circuit.
On detecting a suitable frequency from the 555 Tx, the opamp reacts and generates a low logic at its output pin which might additionally built-in to an external device for the particular functions.
The above circuit could be correctly designed for the suggested train ID detection, and 8 such Rx units could be laid down the tracks, and the 555 Tx units on each of the trains, such that the uniquely picked number of trains with the different Txs are found by the Rx receivers as well as the matching low logic details are deliver to the computer for advising the user relating to their occurrence.