Hi,
I hope someone can help.
I originally took an IR Amplifier circuit that takes a 5v IR signal (from IR extender or USB-UIRT) and amplifies the low power emitter into a high power room blaster. The circuit is here:
I modified the circuit to give me 3 IR LED's in parallel so that my entire room is covered (these are high powered LEDs with 1.2v forward voltage and 100ma forward current), reduced the 15 ohm resistor to 10 ohms and am powering it with a 9v battery instead of the 12v source. I am also using L940-36V IR's and an MPSA13 transistor.
This circuit works perfectly, however I now want to modify it to add a Red LED at the blaster area and another at the power source area with the goal of allowing me to see when an IR signal is emitted. I added one forward voltage 2v Red LEDs in parallel to the other three IR LED's with 400k resistor and the other one in parallel to the circuit with another 400k resistor. However they do not seem to light at all. The circuit tests fine and connecting power to the LED's lights them up, but in the circuit they just will not light up
I've very new to electronics (as you can probably tell) so am probably doing something very silly. Any guidance is most welcome.
Thanks,
Gary