Is it 'legal'? Depends on how you do it. The only people that can just
go off and build a transmitter/transceiver are licensed
"amateur radio service" operators, and then *only* for
equipment that operates in the 'ham' bands. *Everything*
else requires FCC approval, in one form or another -- unless
it is _very_ low power, operating in specified frequency
ranges.

That is NOT true, elsewise how would we be able to build the prototypes that
we test for the type acceptace procedure. That is, if I can't build an
aircraft band transceiver then I can't test it to get type acceptance which
means that I can't produce them, and if I can't produce them, then I can't
sell them... Get the circular argument?

There ARE provisions in the rules for a legitimate manufacturer to build and
test prototypes for licensing procedures.





Is is "practical"? Not if the objective is to save money. It would have
to be 'accepted' by the FCC. Either "type accepted",
which would let you do production-line work, and sell
on the open market, Or _individually_ approved, for
that specific radio only,

I am not aware of anything in parts 1, 15, or 87 that allow single-unit
approvals.



*either*way*, you're looking at costs that are well
into 5 figures. And probably around two years of
paperwork.

Well, not really. I've done half a dozen type acceptances where the costs
(excluding my labor) are well under a thousand dollars. HOWEVER, you have
to be very creative about how you do it.

Jim