[SOLVED] Can we use ir module instead of phototransistor??

[jazeel06]

CAN WE USE IR MODULE INSTEAD OF PHOTOTRANSISTOR IN THE BELOW CIRCUIT....


what all changes should be made if can use ir module instead of phototransistor and bulb...???

pls help me fast...its my mini project

 

[tpetar]

Hi & Welcome Jazeel,


Can you explain circuit ?



I found project located here with explanation :

Electronic card lock system

**broken link removed**

https://circuitdiary.blogspot.com/2011/06/electronic-cardlock-system.html

https://www.way2project.in/projects/2011/04/electronic-card-lock-system/


Of course you can use IR diode but must take care to IR TX and RX are on the same freq.

But system is bad, someone can make card with some papers and open lock. There is better solutions. Circuit is robust and complicated, in other words to many components for small goal.

 

[Arch Zone]

CAN WE USE IR MODULE INSTEAD OF PHOTOTRANSISTOR IN THE BELOW CIRCUIT....


what all changes should be made if can use ir module instead of phototransistor and bulb...???

pls help me fast...its my mini project

No, you can't. IR Module has 30-50 KHz demodulator and the light source's frequency is 50-60 Hz. You have to add modulator if you want to use IR Module.

 

[tpetar]

No, you can't. IR Module has 30-50 KHz demodulator and the light source's frequency is 50-60 Hz. You have to add modulator if you want to use IR Module.

No my friend, IR is just like other wave of light, can light anytime and anywhere (except in black hole), we dont need modulators/demodulators for IR. Infrared wavelength is around 930 nm, 870 nm and 950 nm. If this device or part of device linked with this light section insulated from other light sources then we dont need mod/demodulators. Additional to this, this circuit, especially light section not require some data transfer, it just detect light is present or not, because that they use in original circuit ordinary bulb and photo transistor.

And one correction modulators and demodulators have fixed carrier frequency about 32-56KHz, not 50-60Hz (Very often 38KHz).

 

[Arch Zone]

Mmm.. I'm sorry. But if we talk about IR module, there is a band pass filter inside.

 

[tpetar]

You can use something like this (I give you just example, You should pay attention on voltages and other things):

**broken link removed**



Resistor depends from needed current of IR LED.


I supose main goal is to eliminate light to be seen from device. How I say in post #2 this is not good idea to make door lock with bulb or IR, there is simpler solutions with few parts and with higher security.

 

[FvM]

Mmm.. I'm sorry. But if we talk about IR module, there is a band pass filter inside.

I agrre with your previous statement except for the 50 Hz point, which I understand related to the light source in the original post.

Incandescent light has about no modulation due to the properties of the filament. Fluorescent lamps produce considerable light modulation, but it's 120/120 Hz.

The basic point is, that the said "IR modules" or remote control receivers only work with modulated light. tpetar mentions the same, I simply don't understand what he's complaining about. Apparently he understood "bandpass" as optical filter, which hasn't been said at all.

 

[tpetar]

No, no I dont complaining I just try to understood why he/she whant to use IR instead incandescent light bulb, and I search simpler solution. I just say that is possible to have IR transmission without m/d. Of course he can use modulator/demodulator. I supose main goal is to prevent light to be seen from device. But if we isolate device light section from otside lights and properly adjust sensitivity we dont need m/d.

 

[FvM]

No, no I dont complaining I just try to understood why he/she whant to use IR instead incandescent light bulb, and I search simpler solution.

Yes, that's right of course. Somehow I didn't get the intention of your post. My fault.

 

[jazeel06]

Hi & Welcome Jazeel,


Can you explain circuit ?



I found project located here with explanation :

Electronic card lock system

**broken link removed**

https://circuitdiary.blogspot.com/2011/06/electronic-cardlock-system.html

https://www.way2project.in/projects/2011/04/electronic-card-lock-system/


Of course you can use IR diode but must take care to IR TX and RX are on the same freq.

But system is bad, someone can make card with some papers and open lock. There is better solutions. Circuit is robust and complicated, in other words to many components for small goal.

thank you ..
i know that this is a complicated ckt for simple goal...but i cant change my topic b'cos i already gave this topic to my mini project co-ordinator.he wont allow me to change the topic.
i hope that if i use ir instead of bulb and phototransistor, the size of my project will get reduced..ryt???
can any one tell how can i implement more security option in the above ckt.? without changing this topic...

---------- Post added at 15:26 ---------- Previous post was at 15:21 ----------

can anyone tell how to make the pcb layout of this ckt?
i dint find phototransistor 2n5777 and dpdt 12v relay in orcad 9.1 and diptrace?
help pls

 

[tpetar]

Do You know how to program uC ? Do you whant to learn and try ?

I will help You!

You can make door lock with just one button and 4-digit opening code, or with keypad, or with dongle key,...

 

[jazeel06]

this is not a door lock.
this is used to lock eletronics/electrical appliances.
i told u that i cant change this topic as my mini project.
so i should do electronic card lock as my mini project.

 

[tpetar]

You can use it for different things, door lock is just termin. You can use this things to start or turn off some device or activate some option.

 

[jazeel06]

my theme should be electronic card lock

 

[tpetar]

Did You think to use smartcards ? Maybe that will help you. I send you email with several projects, check it.


Here is one :
**broken link removed**

 

[jazeel06]

Hey can i use spdt relay instead of dpdt relay in the above ckt???