need help with IR circuit plz

[ant9985]

hi, im going to build the circuit in the following link but there is a diode on it which i don't know what to use as all they have writen is 'diode' in the parts list. i was wondering if anyone could tell me what diode would be suitable for 'D1' in the following circuit:

**broken link removed**

 

[0x34]

There is no specification to any particular diode, and looking at the circuit, I'd imagine a 1N914 would be fine.

0x34

 

[Phasor]

Yes, any small signal diode will do. eg,
1N914 (as Ox34 suggested)
1N4148

otherwise, if you don't have any SS diodes handy, a small power diode will be fine, eg 1N400x series

 

[JimB]

otherwise, if you don't have any SS diodes handy, a small power diode will be fine, eg 1N400x series

As the transmitter is sending IR pulses at 5kHz, the diode in the receiver will need to rectify 5kHz, a 1N400x will struggle (fail!) to do so. I think a 1N914 or 1N4148 would be best.

JimB

 

[ant9985]

thnx for the suggestions.

Also does anyone know i could power this device?

 

[Nigel Goodwin]

thnx for the suggestions.

Also does anyone know i could power this device?

Off a +/-12V PSU, as the webpage says.


However, it seems rather overcomplicated, and rather restricted - why not modulate the transmitter IR LED at 38KHz, and use a simple three pin IR receiver IC?.

 

[ant9985]

This sounds a great idea you have nigel. i greatly appreciate the suggestion and you will have to forgive my noobishness but..

how would i modulate the transmitter IR LED at 38KHz. i thought it was the 555 timer that gives out the 5khz square wave and the diode just transmits it to the detector. Also when you say 'simple three pin IR receiver IC' (not sure what IC stands for) do you mean the transistor type? and if you do, do you have any particular model in mind?
Would all this unbalance the circuit so i would have to change other things?

Also i have another question on this circuit: it mentions an IR reflector on the parts list, if im going to put the emitter and detector on two walls either side eg. a door way, with the emitter and detector facing each other, will this mean i wont need the IR reflector?

 

[Nigel Goodwin]

This sounds a great idea you have nigel. i greatly appreciate the suggestion and you will have to forgive my noobishness but..

how would i modulate the transmitter IR LED at 38KHz. i thought it was the 555 timer that gives out the 5khz square wave and the diode just transmits it to the detector.

You simply alter the timing componets, so it oscillates at 38KHz instead of 5KHz - or use an existing circuit on the net (there are plenty of 38KHz 555 circuits about).

Also when you say 'simple three pin IR receiver IC' (not sure what IC stands for) do you mean the transistor type? and if you do, do you have any particular model in mind?
Would all this unbalance the circuit so i would have to change other things?

IC is 'Integrated Circuit', any vaguely modern IR remote control item is almost certain to use a three pin IC receiver. You can check my IR PIC tutorials which use one, or my IR remote tester at .

Also i have another question on this circuit: it mentions an IR reflector on the parts list, if im going to put the emitter and detector on two walls either side eg. a door way, with the emitter and detector facing each other, will this mean i wont need the IR reflector?

The reflector is so you can have both at one side, you won't need it if you fit the transmitter and receiver at opposite sides.

 

[ant9985]

ok thnx a lot for the info

 

[gogo2520]

TFMS5360 IR receiver

TFMS5360 IR receiver
I don't know if I read that number right, i got it off one of your tutorials but I can't find it on the web. I think a PNA4602M dector should work in its place and you can get them at www.glitchbuster.com it runs at 38khz too.
Your tutorials have been a great help thanks Nigel