Pete - don't want to get in a pissing contest.
Caution and sagacity in equal measure.
I'm a qualified timekeeper
I'm a qualified brainsurgeon.
, and the typical error with a novice timer is at least 0.5sec.
OK, I'll bite. What is a "novice timer" and what causes the errors?
I accept the possible limitations of the IR system,
but hope to mitigate [...] by a) using modulated IR
Why will this mitigate the limitations?
by use of directional tube on the receiving side (and possibly the sending side too)
What is a directional tube?
This is part of the point of my project - research as well as implementation.
Ah yes, your project. About that. Which university assigns such a trivial project to "an electronics novice" for a "final Uni project"? Surely not Oxford?
If you have any helpful advice to share based on your experience in this area I would be grateful.
I have been beaten to it, but a small red laser that you can buy at places like Radio Shack will give a beam that has a negligible spread over the distances required by this "project". I'm surprised that a "qualified timekeeper" wouldn't know this.
But why on earth does timing an 8-year old boy (assuming he exists) require such incredible accuracy? One of the arts of being a parent is in creative lying. Use a stopwatch and keep telling him he's doing great.