IR Remote Control Transmitter (September 1996): Transistor Q1 (BC337) was
shown reversed on the PCB overlay diagram. Either fit it with the C and E
leads, or replace with a PN100 transistor fitted as per the overlay. Also R5
should be changed in value to 18k 1%, and R6 should be changed to 100 ohms.
As the IR LEDs are quite directional in their emission, operation may be
improved if the leads of the two LEDs are bent slightly so their beams
converge at a distance of about three metres or so.