Simple remote gopher

[Um...Me123]

Being new to electonics I need some advice on building a very simple remote extender.
I don't know very much about IR (well I'm certainly starting to in other research) or in using transistors and signal recievers.

My seperate question:
When you are using a reciever such as an IR one..it has to leads and looks just like a transmitterr/LED.

 

[boombar]

http://www.mitedu.freeserve.co.uk/Circuits/Interface/irext.htm

 

[Um...Me123]

Couple questions:
If I want to make infrared filters (blocking visible light) I need to get unexposed but developed film? right?  And you use 2 layers?

Is the voltage going to the LEDs (the red and the IR) affected by the opamp (I dont really know anything about them)?  So if i want to use more than one IR LED in parallel (for example) can i mess with the resistor values figuring for 12V in?

If i want more than one recieving diode can i just out more in parallel or do i need to change something?

Where do i find a opamp?  I live in the US and want to get my parts from www.allelectronics.com and if somethings not availiable there, from the local radioshack.  Can someone find an opamp on all electronics for me cause i couldnt and i guess i dont know wha im looking for.

I got to go and i think i have more questions. thanks

 

[audioguru2]

Why not purchase the IR photodiode with the filter built-in?


LEDs shouldn't be connected in parallel because each one is different. To add more then you simply connect them in series then recalculate the new value for their current-limiting resistor.


You can't parallel photodiodes. Each one needs its own opamp circuit. Another opamp can be used as a mixer for them to drive the transistor.


www.newarkinone.com has thousands of the CA3140E opamp for only 55 cents US each. They also probably have everything else you need. ;D