Quote:
Originally Posted by Dave K.
Eric,
Pictures of the radio's internals are part of IFI's FCC OET, EA public file as is the emissions test report performed on a prototype unit.
Based on my own observations of the problem, an Electrical Fast Transients test, such as EN 61000-4-4, might be more revealing than an RF succeptability test, but certainly a lower frequency, 100% AM modulated signal can reveal problems that an EFT test would also expose.
Again, without motors running, we saw no indication of packet loss.
Our build location is surburban with no close field radiators, let alone any dynamic radio transmission that would be tightly coupled to motor actuations.
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The comment about cracking the box was in regard to seeing if the automatic gain control (assuming the IFI RF frontend was using this) was kicking in to some unknown response. With a few oscilloscope leads we could check to see if this was occurring.
We performed no lab testing before shipping the modem back, so other than some more recent comments about potential motor interference the only thing I had to go on was the cell phone comment. It seems unlikely to me as well, but if I'm scanning at 30MHz it's just as easy to let the equipment continue up to 900MHz. Our Biconilog antenna is good to 1Gig, and somewhat shoddy to 3Gig. From 3-9 I've got a log antenna, and past that you'd need a horn which doesn't calibrate well for the 10m FCC testing we typically perform.
I'm pretty limited in the EFT testing I can perform, however we have some loops lying around that might work, albeit in a completely non-calibrated fashion. Certainly anything I try in that realm will be pretty non-scientific.
If IFI chooses to end speculation after a few more radios have been in their lab, that would be fantastic. Like last year's 8.2V problem, there were some intelligent discussions trying to determine what the problem is. The more people with something useful to contribute looking at the problem, the better.
Ninja Edit: Thanks for filling in the details of our acronym-laden conversation Dave. I tried to give some detail to my earlier posts so this doesn't lose meaning to others following the thread.