Simple IR repeater

[RGV250]

Hi,
I have a need to duplicate an IR TV remote signal, it is only going 1mtr or so.
I wondered if I could get away with just connecting a 38khz IR receiver output (like TSOP38238) to a standard IR diode. It looks like the TSOP can only output 5ma so would probably need to add a transistor in between.

Do you think this is possible?

Regards,
Bob

[Wimax]

Hi Bob,

I think that using a TSOP38238 you need to restore the IR beam modulation before driving a high efficiency IR TX LED (with a transistor) using an MCU or other solutions.

[top204]

If it is just to extend the IR remote's range, use a pair of op-amps with an IR sensor and an IR LED.

Make the op-amps into a non-inverting amplifier with a buffer, and add some gain. For a bit of an extra push, use a transistor at the output of the op-amp, or use one of the higher powered op-amps.

The modulation will not be removed and the signal will be the same coming out as it was going in, just a lot stronger.

[Wimax]

If it is just to extend the IR remote's range, use a pair of op-amps with an IR sensor and an IR LED.

Make the op-amps into a non-inverting amplifier with a buffer, and add some gain. For a bit of an extra push, use a transistor at the output of the op-amp, or use one of the higher powered op-amps.

The modulation will not be removed and the signal will be the same coming out as it was going in, just a lot stronger.

Certainly the most immediate solution if you don't have to demodulate the signal, the TSOP38238 costs very little and has what you need to receive the IR signal inside, but you are then forced to remodulate 'complicating' the circuit a bit, thus defeating the concept of 'simple' and 'cheap'.

[top204]

You can't get much simpler than an op-amp non-inverting amplifier. :-)

Although, a couple of transistors used as common emitter and non-inverting buffer would do the same task, and the transistor pair would also drive the IR LED, because they need quite a large current for range.

[dnaci]

There is a repeater circuit using pic12f675 processor in the link. Source code asm.

http://picprojects.org.uk/projects/miniprojects.htm#IR%20Remote%20Control%20Repeater

[RGV250]

Hi dnaci,
That little project looks like what I am after, I have found something on eBay or Amazon but will be better to make one myself.

Bob

[diebobo]

I checked my IR repeater code made 12 years ago, and the active part is realll simple..

Code Select Expand

If IR_RX_1 = 0 Or IR_RX_2 = 0 Then
            HPWM 1,85,37600
        Else
            HPWM 1,0,38000
        End If
This was al that makes it work, 2 receivers. Thoose 38 kHz ones which just spit out a 1 or 0 demodulated signal.