Here's what I just heard back from SPOT

Hello Mr. Long -

Thank you for your feedback.

We've had some clarification when it comes to the usage of SPOT while other
GPS devices are present. What is advised is that you don't use the SPOT
unit within a few feet of a GPS device. The distances you mentioned
completing successful tracking ? (9 feet with a handheld GPS device and 4
feet for VHF radio) is sufficient and the general rule of thumb for your
review purposes.

We have had very successful aviation and marine use of the unit.

We hope that clarifies the issue of the units use. If you have any other
questions, or concerns, please don't hesitate to ask.

Best Regards,


SPOT Customer Service



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Roger Long