> What is the biggest problem encountered with the devices themselves and
> also, the biggest problem encountered when trying to source them.

1. Price. Some importers like to mark up products in ways I prefer not to
describe. Here a SIPP module and a keyfob tx are sold for the equivalent
of $100 (they list for ~$30 elsewhere if I am not wrong). Prevent this by
making sure that advertisements include the price and emphasize easy
delivery to wherever your clients are.

2. The lack of a well known protocol and modulation technique that can be
used as a 'plug in' with minimum effort. Everyone roll their own and
reinvent hot water and the wheel every time. Many times the water is not
so hot and the wheel is not so round. There were several relevant threads
on this list in the past imho.

$0.02,

Peter

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