I suspect that Nikon chose IR for its CLS technology to avoid the problem of building three slightly different models for the three different frequency sets in use: Japan, North America and Europe.
Wouldn't it be fairly straightforward to build one model with an SD, or similar, card slot that provides the frequencies? Or, even simpler, a switch with three positions that specify the frequency set? The folks at Pocket Wizard build three(?) different hard wired models. There must be a simpler way.
One drawback to this idea how to prevent people from using the incorrect frequency cards/switch settings when traveling in other countries.
I will pass your suggestion for a DIY forum along to the founders.
Thanks for your comments in this interesting thread.
HBB in Phoenix, Arizona Nikonian Team Member
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