[keiths]

Thanks for all the information, and I will be onto PSR to order the chip. I may for I think £2.40 also get the spare IR LED, reason being my track uses the Scalextric Lap game -albeit with the tower wired remotely as on a scenic layout it looks more than a little daft and toy like, which is not surprising given that what is! The track sensor for this is certainly not the most reliable, often having difficulty registering with some older C7005 chips, so it may have trouble picking up the Slot it board mounted LED. As I say for £2.40 better to be safe...
Thanks again...