WOW. This was a trip back in time. 45 years to be exact. I helped design and build a vehicle detection circuit using an inductive loop. It was based on 2 colepitts oscillators locked together. The loop was the coil in the road and the adjustment on the second oscillator was a wound coil and a ferrite threaded slug to tune the loop. The system could be set up by just chucking a loop of cable in a rough 4 x 4 foot square 2 turns on the ground. Tuned in set up. Small shorted coil in my shoe worked.
Great presentation. I have always been interested in signal loop detectors as I notice the devices everywhere. Most I observed are data collectors and loop induction circuits as well. Very interesting.
you can see the cutouts in the asphalt and concrete at intersections you'll see saw marks where they cut grooves in the road and installed the wire and used polyurethane sealant to seal it and you can see those cuts leading to the curb to the traffic light junction box!
You could also use the loop to form an LC oscillator and then detect a rapid change in frequency as a vehicle passes over the loop. This approach has the benefit of rejecting long term drift in the tank circuit.
I wonder if I could use a micro controller to self calibrate the loop? Adjust the frequency till the A/D sees the highest voltage and then look for a significant drop in voltage to determine presence. I'm thinking it may be able to self calibrate occasionally to adjust for temperature/humidity and other things that might affect the resonant frequency.
Thanks for nice video! I always know that working like antenna but never to look on internet to see what is like and how circuit works exactly. Now is clear. Thanks!
Do you need to be an electrical engineer to fully understand circuits like this . I may decide to study electronics . How many years of study or experience does it take to read these type of schematics? Very cool sir 😎
what normal/average volt change if metals detected, in your experiment, and how to make stable power input in LM393 pin 6, if metals detected. Thank you very much.
Just a question. I have this system in my garage, the question is how do I trigger the loop using my bicycle? I don't want to bring the fob with the bicycle. The garage gate opens automatically from inside with the car, I would like to be do it with the bicycle. Thank you
This is basically working on the principle of inductance, right? So introduction of any ferromagnetic material in the loop or inductor will give birth to change in magnetic flux and that will eventually generate the induced current that will on the buzzer or alarm. Is it so, right! So if a vehicle comes and stops right at the loop, initially it will generate current/induced current due to change of flux but after this, since the vehicle is stopped and magnetic current is not changing so not current will be induced, then what will make it to keep the buzzer on and that vehicle has gone or stopped?
I notice that the wire from the loop to the circuitry is straight......I've been advised that the wire from my loop to the circuitry should include at least 25 turns per foot....and no mention of a capacitor on the loop...just wondering how these differences might affect stability or sensitivity......im using a FAAC Proloop
Sir, I'm excited with this project. I wanna ask you something. Is the cable (that used for the loop) is just 1 cable or 2 cable? If it's 1 cable, then just connect the end of each side to the capacitor that connected to the cable from the circuit, am I right?
I am making a smart parking system and I am new to this and I want to know the part where in the schematic a coil is represent ed in bottom left, is that the induction loop of 6 feet length?
@Trijit Das, a couple of important factors to consider. (1) In a multilevel car parking system, you will have serious interference from the iron in the concrete, (2) stability will be an issue with temperature, vehicles may get detected in the mornings and by evening, you will not be able to detect a few type of vehicles. How do I know, been there, done that, in case you want more info, drop me a mail on madhavdivya@gmail.com
This ground loop system works very well for vehicles. It does not work well with bicycle though. Can you please advise cyclists how to get the bicycles detected by the loop? Sometimes, i ride on the edges of the rectangle and it works. Sometimes it don't. What kind of modification can i make to my bicycle in order to be detected better by the loop?
Neodymium magnet on the bottom. Get a nice strong one and either glue, or tape, or otherwise fasten the magnet to the chassis. Theres a video by kipkay on it. Just look up triggering green lights by him. You can learn more about how it works on howstuffworks.com, its a site I frequently use and I found an article on it about traffic loops.
but why will the voltage drop ? as the inductance will increase , the resonating frequency changes and it doesnt match with the square wave frequency. this is a possible answer from my side ..
It has been 1 1/2 yrs since I made the video, so I don't recall all the details, but in order for the circuit to trigger, pin#6 must drop below the reference voltage of pin#5. Thanks For Watching!
Hello I really need help regarding your circuit. I have made it and it worked fine for once, but then it has stopped working. The voltage point that goes on the 6th pin of the LM393, doesn't go below 9 volts for any values of R set in the potentiometer. hence, the final output of the lm393 on the 7th pin is always low. What i figured out was that the inductor gets short circuit after it is fully charged and current flows through it.
I know its been a long time since this was done, but does the power supply have to regulated? Can I use a standard battery to power the circuit? What would happen if I used an unregulated 9v power supply?
Hi. Use a regulated power supply for stability. Thanks for watching! Be sure to check out my extensive video playlists for other great videos of interest to you, rate thumbs up, and share.
Can I buy this circuit and loop ...?i want use it as entrance indicator when any car pass the gate of my farm Ana activate Alarm system .please advice thank
Hello. I don't sell circuits/kits. I only show others how to make them. You can try contacting Gary at his website in the video description area to see if he can sell you a kit. Be sure to check out my video playlists, rate thumbs up, subscribe, and share my channel with others. Thanks!
Hi, I have followed Gary's circuit sometime ago for my daughter. I had a problem with the RCC flooring with the metal in the concrete interfering with the circuit. Have you come across such issues anywhere and how did you solve if you have come across such.?
What is the voltage difference on pin 6 of the LM393 that you detected when the vehicle is over the loop? I need to make a 10 meter x 1 meter loop to detect 3 forklifts on it, but during testing I detected a drop of only 50mV when the vehicle is over the loop. What could be modified in the circuit to increase this voltage drop to values greater than or equal to 0.5V? Congratulations on the channel.
Unfortunately this particular circuit has been put into storage, so I cannot perform any tests. I can assure you the circuit does work well when properly constructed.
Can I make the coil in oval or rectangular shape, would it affect the system, because I only have to detect the presence of metal, not any accurate reading or something.
Hi I am using a 1.5 mm copper wire for making the coil, which I calculated gives 50 henry inductance theorotically. But I do not have an inductance meter to calculate the inductance of the coil, so how can I measure the inductance of the coil? Also, does the wire used for the coil need insulation ? I made the circuit but somehow it ain't working.
Make sure you duplicate everything exactly as I did, and use the same materials/components. The wire for the coil must have insulation, otherwise each turn will be shorted against the adjacent turn.
I have had problems with the circuit, it doesn't work, the piezo electric alarm is always activated. The only thing that differentiates my circuit from yours is a potentiometer of 5k instead of 2.5k. Is that the problem?
Hi again, actually, the circuits works but it didn't have a long range detection, i have to touch the metal to the spira. How can I improve it?. Do I need the 2.5 k potentiometer? Or just playing with the values of Cx and L1? . What do you advise me?
Nice work man! But I have a doubt, what is the real value of the capacitor that is located between the diode and the coil? Is 0.01 u or n? And what is the value in A of the power source of 12V? thanks !
hai, on your video i see you use zener diode, but refer to your schematic you out diode 1N4148 .................. which one is thru ............... tq.
hey i am able to detect metal and get a 12v or 0 v output on pin 7 of lm393 comparator, but i want to convert this 12 volts into 5 volts. So for that i am using 7805 voltage regulator. But it happens so that if i connect the 7805 to pin 7 or even the transitor that you have in your circuit, the voltage on pin 7 drops to 3v when metal is detected(which should be 12 v actually). Can you please suggest something which can solve this problem of voltage drop. Any help would mean a lot. Thanks in advance. :) your circuit is working great other ways! Helped a lot in my project.
Use a simple voltage divider if all you want is a 5mA / 5V output to trigger another circuit(Logic). Take pin #7 and connect it to 1.4k ohms, then from the 1.4k ohms connect a 1K ohm resistor to Batt NEG. The 5V output will be BETWEEN the 1.4K and 1K values.
somebody must be getting a lot of kickbacks from these loop detectors; green wave or synchronized traffic coordination for smooth flow control is so much better, simpler, and makes more sense, but common sense is not so common these days anymore.
There's no privacy anymore. Newer vehicles have RFID built into the valve stem to report air pressure to the vehicle's dash board. Not only can you simply detect the presence of a vehicle but also ID it by reading its built in pressure gauges with an interrogator embedded in the concrete/asphalt. I bet you're one of those electronic geniuses in Columbia Maryland spying on Americans for the NSA. Someone's been letting the horses and cattle out of the pastures onto the road. I'm installing one of these so I can catch the basturd(s) and put a 12-gauge (not AWG) where the sun ain't be shining. I'll upload a video of them using g a colostomy bag cause they's not going to have no butt.
I have some questions about ut schematic 1. Are you using elco capasitor at NE555 ? 2. I hv tried make loop from non solid cable, should I try with solid or another cable ? 3. What kinds capasitor do u use in parallel with the loop ? Or can I get ur list of components? Send me an emali at wahyuzaldi@gmail.com 4. Can I change the diode of 1N4148 ? Bcz the voltage from the loop as a sensor don't change. Thanks I hv tried a month to make this.
Well, if your not into electronics, or have ADD, then yes, it is boring. As you can see 41 people liked it. I suggest you stick to music and learn to be more kind to people that take the time to make these videos to help others.
electronicsNmore Nephtali is a crusty douche bag full of his mother's used tampons and dog excrement. Mr Romero pees himself and smells like a hobo so its understandable he's bored by 555 timers, resonant frequencies, and inductance loops.
+Jeremy Horne +Nephtali Romero Jeremy, don't do whatever you're doing on the floor anywhere near Nephtali. There's a urine puddle there and puss leaking from herpes cold sores. Never dis (disparage/disrespect) an inductance loop. It just ain't right.
WOW. This was a trip back in time. 45 years to be exact. I helped design and build a vehicle detection circuit using an inductive loop. It was based on 2 colepitts oscillators locked together. The loop was the coil in the road and the adjustment on the second oscillator was a wound coil and a ferrite threaded slug to tune the loop. The system could be set up by just chucking a loop of cable in a rough 4 x 4 foot square 2 turns on the ground. Tuned in set up. Small shorted coil in my shoe worked.
Great presentation. I have always been interested in signal loop detectors as I notice the devices everywhere. Most I observed are data collectors and loop induction circuits as well. Very interesting.
Thanks for watching! Be sure to check out my extensive video playlists, rate thumbs up, and share.
you can see the cutouts in the asphalt and concrete at intersections you'll see saw marks where they cut grooves in the road and installed the wire and used polyurethane sealant to seal it and you can see those cuts leading to the curb to the traffic light junction box!
You could also use the loop to form an LC oscillator and then detect a rapid change in frequency as a vehicle passes over the loop. This approach has the benefit of rejecting long term drift in the tank circuit.
They'll think twice before driving there again! Another great video.
I wonder if I could use a micro controller to self calibrate the loop? Adjust the frequency till the A/D sees the highest voltage and then look for a significant drop in voltage to determine presence. I'm thinking it may be able to self calibrate occasionally to adjust for temperature/humidity and other things that might affect the resonant frequency.
Thanks for nice video! I always know that working like antenna but never to look on internet to see what is like and how circuit works exactly. Now is clear. Thanks!
Thank You. The circuit works well.
Do you need to be an electrical engineer to fully understand circuits like this . I may decide to study electronics . How many years of study or experience does it take to read these type of schematics? Very cool sir 😎
1 year as a selftaught diy and 2 years through college.
I replaced the LED with the piezo alarm. You can use an LED if you'd like.
what normal/average volt change if metals detected, in your experiment, and how to make stable power input in LM393 pin 6, if metals detected. Thank you very much.
Love it.... I've been looking for it.... Thank's electronicsNmore !
You're welcome! There are many excellent circuits shown on this channel. Be sure to share my channel with others and rate thumbs up. Thanks
Just a question.
I have this system in my garage, the question is how do I trigger the loop using my bicycle?
I don't want to bring the fob with the bicycle.
The garage gate opens automatically from inside with the car, I would like to be do it with the bicycle.
Thank you
It won't be sensitive enough for a bike. The loop would need to be much smaller.
Thank You
This is basically working on the principle of inductance, right? So introduction of any ferromagnetic material in the loop or inductor will give birth to change in magnetic flux and that will eventually generate the induced current that will on the buzzer or alarm. Is it so, right!
So if a vehicle comes and stops right at the loop, initially it will generate current/induced current due to change of flux but after this, since the vehicle is stopped and magnetic current is not changing so not current will be induced, then what will make it to keep the buzzer on and that vehicle has gone or stopped?
Yes, inductance. :-)
you are doing great job so keep it up
Thank You. As long as my viewers continue to share my channel with others and watch my videos, I will continue to upload.
I notice that the wire from the loop to the circuitry is straight......I've been advised that the wire from my loop to the circuitry should include at least 25 turns per foot....and no mention of a capacitor on the loop...just wondering how these differences might affect stability or sensitivity......im using a FAAC Proloop
You mean twist the straight wire 25 times per foot? Mine works just fine w/o doing that.
i love ur videos....great work
Great to hear! Be sure to share. Thanks
thank you....great job....
Your welcome. Be sure to check out my video playlists.
Sir, I'm excited with this project. I wanna ask you something. Is the cable (that used for the loop) is just 1 cable or 2 cable? If it's 1 cable, then just connect the end of each side to the capacitor that connected to the cable from the circuit, am I right?
The wire is a single conductor. Follow the schematic, it shows where to connect. Thanks!
@@electronicsNmore sorry, I'm a newbie. I wanna ask you, where to connect the ground?
I am making a smart parking system and I am new to this and I want to know the part where in the schematic a coil is represent ed in bottom left, is that the induction loop of 6 feet length?
@Trijit Das, a couple of important factors to consider. (1) In a multilevel car parking system, you will have serious interference from the iron in the concrete, (2) stability will be an issue with temperature, vehicles may get detected in the mornings and by evening, you will not be able to detect a few type of vehicles.
How do I know, been there, done that, in case you want more info, drop me a mail on madhavdivya@gmail.com
Is it possible to change (increase) the sensibility by making changes in the coil? I think that more Henrys = Higher sensibility. Am I right?
You can adjust the sensitivity, but there's no need to, it works fine as shown. Thanks for watching!
This ground loop system works very well for vehicles. It does not work well with bicycle though. Can you please advise cyclists how to get the bicycles detected by the loop? Sometimes, i ride on the edges of the rectangle and it works. Sometimes it don't. What kind of modification can i make to my bicycle in order to be detected better by the loop?
Neodymium magnet on the bottom. Get a nice strong one and either glue, or tape, or otherwise fasten the magnet to the chassis. Theres a video by kipkay on it. Just look up triggering green lights by him. You can learn more about how it works on howstuffworks.com, its a site I frequently use and I found an article on it about traffic loops.
but why will the voltage drop ?
as the inductance will increase , the resonating frequency changes and it doesnt match with the square wave frequency.
this is a possible answer from my side ..
It has been 1 1/2 yrs since I made the video, so I don't recall all the details, but in order for the circuit to trigger, pin#6 must drop below the reference voltage of pin#5.
Thanks For Watching!
Hello
I really need help regarding your circuit. I have made it and it worked fine for once, but then it has stopped working. The voltage point that goes on the 6th pin of the LM393, doesn't go below 9 volts for any values of R set in the potentiometer. hence, the final output of the lm393 on the 7th pin is always low. What i figured out was that the inductor gets short circuit after it is fully charged and current flows through it.
Please refer to my pinned comment.
I know its been a long time since this was done, but does the power supply have to regulated? Can I use a standard battery to power the circuit? What would happen if I used an unregulated 9v power supply?
Hi. Use a regulated power supply for stability. Thanks for watching! Be sure to check out my extensive video playlists for other great videos of interest to you, rate thumbs up, and share.
Can I buy this circuit and loop ...?i want use it as entrance indicator when any car pass the gate of my farm Ana activate Alarm system .please advice thank
Hello. I don't sell circuits/kits. I only show others how to make them. You can try contacting Gary at his website in the video description area to see if he can sell you a kit. Be sure to check out my video playlists, rate thumbs up, subscribe, and share my channel with others. Thanks!
Hi, I have followed Gary's circuit sometime ago for my daughter. I had a problem with the RCC flooring with the metal in the concrete interfering with the circuit. Have you come across such issues anywhere and how did you solve if you have come across such.?
You cannot use this circuit on a concrete driveway with wire mesh or rebar. You need to use a blacktop driveway, dirt road, or gravel.
But surely, there should be a way out. Can you please give it a thought, in your free time?
I need to build this on a smaller scale. How would I change it so that it would detect a small metal object?
Smaller diameter ground loops detect smaller objects. You need to experiment.
What is the voltage difference on pin 6 of the LM393 that you detected when the vehicle is over the loop?
I need to make a 10 meter x 1 meter loop to detect 3 forklifts on it, but during testing I detected a drop of only 50mV when the vehicle is over the loop. What could be modified in the circuit to increase this voltage drop to values greater than or equal to 0.5V?
Congratulations on the channel.
Unfortunately this particular circuit has been put into storage, so I cannot perform any tests. I can assure you the circuit does work well when properly constructed.
Thank you very much . Can I use a coil not in a circular as a line coil I mean in line not circular.
The loop can be cut into concrete/asphalt the same way loops are cut for traffic lights. Rectangular shape with the corners cut at angles.
Can I make the coil in oval or rectangular shape, would it affect the system, because I only have to detect the presence of metal, not any accurate reading or something.
Yes rectangular or oval works.
@@electronicsNmore Thanks a lot sir !
Very interesting video. Is this related to a piezoelectric sensor?
No, it's inductive.
Good tutorial!
Thank You!
Be sure to share my channel with others, and rate Thumbs Up.
Great job again.
what is loop size? and how many times turn loop?
Hi
I am using a 1.5 mm copper wire for making the coil, which I calculated gives 50 henry inductance theorotically. But I do not have an inductance meter to calculate the inductance of the coil, so how can I measure the inductance of the coil? Also, does the wire used for the coil need insulation ? I made the circuit but somehow it ain't working.
Make sure you duplicate everything exactly as I did, and use the same materials/components. The wire for the coil must have insulation, otherwise each turn will be shorted against the adjacent turn.
Thank you very much. Also, I just want to glow the LED whenever a car passes through, so can I skip the transistor and relay part of the circuit?
I have had problems with the circuit, it doesn't work, the piezo electric alarm is always activated. The only thing that differentiates my circuit from yours is a potentiometer of 5k instead of 2.5k. Is that the problem?
Try adding a 2.7k resistor in series with the POT.
electronicsNmore Instead of 2.5k right?
Hi again, actually, the circuits works but it didn't have a long range detection, i have to touch the metal to the spira. How can I improve it?.
Do I need the 2.5 k potentiometer? Or just playing with the values of Cx and L1? . What do you advise me?
Nice work man! But I have a doubt, what is the real value of the capacitor that is located between the diode and the coil? Is 0.01 u or n? And what is the value in A of the power source of 12V? thanks !
Jesús Raymundo Ramos Montaño Thanks (.01uF). The current draw on the power supply is not a lot. I do not have the exact figure.
Ok man, thaks a lot!!! You're my idol!!
very, very nice. well done
Hello
What should we do if we do not get an exact 50 uH value for the inductor coil that we make?
Does not have to be exact.
I have an inductor of 500 uH, what value in the potentiometer should i set to detect a vehicle?
hai, on your video i see you use zener diode, but refer to your schematic you out diode 1N4148 .................. which one is thru ...............
tq.
3.3V zener is off pin #5 on the LM393 IC. 1N4148 or iN4003 to 1N4007 across the relay coil.
Hey can I interface this with Arduino Board? can you help me with the list of components used in this (exact names)?
A link to the schematic should be in the video description area. Thanks for watching!
thank you so much you really helped me thank you
Glad I was able to help. Be sure to rate a "Thumbs Up", and share my channel with others.
Thank You!
Can the zener diode be replaced by a trimpot? Thanks.
Henry Retter Hi Henry. No to your answer.
hey
i am able to detect metal and get a 12v or 0 v output on pin 7 of lm393 comparator, but i want to convert this 12 volts into
5 volts. So for that i am using 7805 voltage regulator. But it happens so that if i connect the 7805 to pin 7 or even the transitor that you have in your circuit, the voltage on pin 7 drops to 3v when metal is detected(which should be 12 v actually). Can you please suggest something which can solve this problem of voltage drop. Any help would mean a lot. Thanks in advance. :) your circuit is working great other ways! Helped a lot in my project.
Use a simple voltage divider if all you want is a 5mA / 5V output to trigger another circuit(Logic). Take pin #7 and connect it to 1.4k ohms, then from the 1.4k ohms connect a 1K ohm resistor to Batt NEG. The 5V output will be BETWEEN the 1.4K and 1K values.
Thank you very much. Helped a lot and its working! :)
Thanks for sharing works good
how much Watt 150 ohm resistor you used,.. because i use 1/4 wat its too hot..
I have no idea why that 150 ohm resistor on pin 3 would get hot. Sounds like a fault in your circuit. .
Yes, even I am having the same problem. Could you solve it?
Miloni Mehta Something not right with your circuit.
thanks you ...................... good job
Ramli Rahman Thanks for watching!
very helpful video..Thanq electronicsNmore
You're welcome! Be sure to rate thumbs up and share with others.
thank you...
Cool 😎
very cool.
Thanks For Watching!
somebody must be getting a lot of kickbacks from these loop detectors; green wave or synchronized traffic coordination for smooth flow control is so much better, simpler, and makes more sense, but common sense is not so common these days anymore.
hey Team!
Thanks for watching Giannis!
Can you send me the diagram
It's either in the video or in the video description area
There's no privacy anymore. Newer vehicles have RFID built into the valve stem to report air pressure to the vehicle's dash board. Not only can you simply detect the presence of a vehicle but also ID it by reading its built in pressure gauges with an interrogator embedded in the concrete/asphalt. I bet you're one of those electronic geniuses in Columbia Maryland spying on Americans for the NSA.
Someone's been letting the horses and cattle out of the pastures onto the road. I'm installing one of these so I can catch the basturd(s) and put a 12-gauge (not AWG) where the sun ain't be shining. I'll upload a video of them using g a colostomy bag cause they's not going to have no butt.
I have some questions about ut schematic
1. Are you using elco capasitor at NE555 ?
2. I hv tried make loop from non solid cable, should I try with solid or another cable ?
3. What kinds capasitor do u use in parallel with the loop ?
Or can I get ur list of components? Send me an emali at wahyuzaldi@gmail.com
4. Can I change the diode of 1N4148 ? Bcz the voltage from the loop as a sensor don't change.
Thanks
I hv tried a month to make this.
Link to the schematic is in the video description area. Everything you need to know is shown. Solid or stranded wire will work. Thanks
thanks, it`s work (y)
this is very boring!
Well, if your not into electronics, or have ADD, then yes, it is boring. As you can see 41 people liked it. I suggest you stick to music and learn to be more kind to people that take the time to make these videos to help others.
electronicsNmore Nephtali is a crusty douche bag full of his mother's used tampons and dog excrement. Mr Romero pees himself and smells like a hobo so its understandable he's bored by 555 timers, resonant frequencies, and inductance loops.
what and you are a gentlemen?
+Jules Bartow ROFLMFAO :-)
+Jeremy Horne +Nephtali Romero
Jeremy, don't do whatever you're doing on the floor anywhere near Nephtali. There's a urine puddle there and puss leaking from herpes cold sores. Never dis (disparage/disrespect) an inductance loop. It just ain't right.
u I