HP 50g/HP 49g+/HP 39gs Battle of the beams -- Increasing IR communication range

[Dimitri]

Interesting. If the calculator is IrDA compliance, the wavelength of the infrared diode should be between 850 nm and 900 nm. Hoping the 50G, the 49G+ and all other calculators use the same wavelength to maximize the communication range.
The HP48S(X) anf HP48G(X) use a 940 nm wavelenth.
Another problem is the emplacement of the emitter and the receiver IR diode. They are inverted between the 48S/G and the 50G.