IR Obstical detector problems

[Kingpin094]

First off, I am building an IR sensor for a robot that is like the 12C508 one that the DARG
(**broken link removed**). I am using a 16F628 to control basically 2 of those circuits.
i.e. I have four leds and 2 ir recievers. The recievers are locked at 56kHz. The code that I have works
greate at producing the ir pulses (600us bursts).

Problem: Anytime I trigger the ir leds the sensors trigger as if they recieve the 56kHz signal.
They trigger even if a take the leds out of the circuit. I have .1uF caps at Vcc and gnd to all chips
and recievers. I am using transistors to boost the power delivered to the leds. Could that be were
my problem is? I know that the triggering is caused by the 56kHz signal leaking from some where.
Does anyone have any ideas on how I can stop the false triggereing.

Thanks ahead of time.
kingpin094

 

[Nigel Goodwin]

Problem: Anytime I trigger the ir leds the sensors trigger as if they recieve the 56kHz signal.
They trigger even if a take the leds out of the circuit. I have .1uF caps at Vcc and gnd to all chips
and recievers. I am using transistors to boost the power delivered to the leds. Could that be were
my problem is? I know that the triggering is caused by the 56kHz signal leaking from some where.
Does anyone have any ideas on how I can stop the false triggereing.

Do you have the IR receivers fed through resistors, with decoupling capacitors after them (see my tutorial hardware pages for a diagram). It's pretty essential to do this, every commercial application I've seen does so.