Scott said:
Household. There would certainly be some commercial/industrial usage, but
more often hobbyists in a home environment.
Power will be supplied through USB connection (5 volts) or external supply
for standalone operation - generally an off-the-shelf 9v wall wart I expect.
Maximum input voltage would be maybe 14 volts. The majority of the
internals will run at 3 volts. Haven't chosen a regulator yet, but it won't
be anything elaborate. No plans for internal batteries at this point.
It could connect to a PC through USB or RS-232, GPS receiver through RS-232,
and VHF or UHF radios through an audio cable. It's got an SD/MMC flash card
slot for removable storage.
By only using low voltage to be supplied from external,
you already offloaded the power line spike tests.
Next then is radiated and conducted emission as well as
radiated and conducted susceptibility to RF from DC to
3GHz. There, your working device with its standard
connectionsis subject to
1) radiation in the mentioned frequency range on cable
or through the antenna. The device has to keep on
working.
2) the radiation of your device on cable as well as on
cable is measured and some values not to be exceeded.
Power and signal lines can be made to conform by shorting
the RF to the case with 100nF caps for DC and smaller ones
depending on the signal frequency. Oops, household cases
are usually not from metal.
Industrial metal cases have to be earthed.
Household cases are usually from plastic, this is somewhat
harder to shield.
Rene