[aprssig] Tesla Field Day mode (or any EV/Hybrid)

[Nick Waterman]

Ev Tupis wrote:
>> Pat, the owner, doesn't operate HF mobile, but we might try some 
>> experiments if we can borrow an HF whip from another club member 
>> sometime. Probably not in the next few weeks due to other 
>> priorities.
> 
> **** If Pat doesn't operate HF, then using his experience doesn't 
> apply to this discussion.

It DOES apply to this conversation. It may not apply to YOUR BIT of this
conversation, but this is a larger conversation with a larger group of
people, who have raised many questions about EV QRM in general, not
specifically HF and not specifically when moving (heck, the thread has
FIELD DAY in the subject line, so arguably our FD experience is VERY
relevant). You'll notice I answered a whole bunch of other people's
relevant questions in the same email too.

Furthermore, if a vehicle was producing noisy wide-band emissions (such
as those typical in commutating motors, many alternators, distributors,
or spark-gap transmitters including spark plugs) they would also likely
affect VHF too. Pat operates local VHF absolutely fine, so for now we
can conclude that EMC/QRM issues from his Outlander PHEV, IF THEY EXIST
AT ALL, don't seem to affect VHF, and anecdotally "old cars" produce
more QRM than his particular PHEV.

If/when we get an opportunity to borrow an HF whip and experiment
further, we can elaborate further. In the meantime sweeping
generalisations like "An entire class of mobile vehicle cannot be used
for HF Emergency Communications" feel unconstructive unless you can
provide experimental data, or even anecdotal evidence, preferably
listing particular models that do/don't seem to have QRM issues, not a
somewhat undefined "entire class".

Come to think of it, there's an EV test drive centre a couple of hours
away, where one can try out an "entire class" of vehicles. I wonder if
we could take an HF rig + whip over there to widen the experimental
scope even further?   :-D

> VHF operation and operation from rigs that are located outside of the
> vehicle and relying on it only for power has never been reported as a
> problem.

So when I said "we might try some experiments if we can borrow an HF
whip", you'd appreciate that, or no? And in the meantime is it not OK
for me to give a specific counter-example or two?

> Part 15 exemptions: What's part 15?.... **** FCC Part 15 rules apply 
> to devices whose purpose is something other than radiating RF, 
> however do so as a consequence of their normal operation.

Again, you appear to have missed the larger point here, which is that US
law has no jurisdiction in the other 95% of the world. Other legal
jurisdictions don't have your "part 15". They have other EMC/QRM
regulations, and MOST of the car manufacturers have been working well
within those rules for decades now. If you're buying a European or
Japanese car, there's a good chance it already had to pass far more
stringent EMC regulations than your "part 15" for their own domestic
markets. "Part 15" and "part 15 exemptions" aren't a thing anywhere else
in the world.

> It is time to revisit that exemption (or...require manufacturers to 
> offer a "low RF emissions" mod...if even for an additional cost).

Absolutely... And I'd posit that you'll find quite a few non-US vehicles
already have those "low RF emissions" mods as standard, because that's
how they were already built for EU/Asia/Pac or even the rest of N/S America.

73! Nick VA3NNW

-- 
"Nosey" Nick Waterman, VA3NNW/G7RZQ, K2 #5209.
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