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Anyone have a VHF/UHF transceiver in their car? If so, any RFI problems?

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I have been procrastinating on doing anything with mine but plan to soon. :) The only thing I have found in the trunk is the power to the hatchback lift. If I had power in the Frunk, I am thinking that would work a lot better for me. I don't know where the 50A terminals might be in the Frunk. However, I have a mode S the X may be different.

We should certainly stay in touch and exchange information. :)

Mark - WB5SLA

Oh, and re: the battery terminals, it turned out to be an easy task. Did scare myself shitless removing the negative terminal to a disheartening display of sparks; but none of the electronics in my car appear to have been affected whatsoever. I was worried about inconsistent transient voltage when it was sparking, but … everything seems fine. The terminals are located as photographed in my other thread; feel free to message me if you want to chat about the particulars.

I have a ID-5100 which needs to be installed in my Classic MS85. I have not pulled the trigger on the install just due to procrastination on my part. I am wondering if we should't have a Amateur Radio specific thread started under general and cover all Tesla models. That would be one place we could go to cover anything Amateur Radio and perhaps GMRS as well.. Thoughts? I am not sure how we could coordinate and get the word out. Perhaps one of the Admins would have some thoughts on how to do this and still be within the rules of the Tesla Motors Club forum guidelines.

I think this thread is more than enough. It's not exactly an extremely popular hobby anymore. ;)

Just keep this thread bumped, perhaps.
 
Wow, one of my first threads on this forum resurrected...

I wound up selling my VHF stuff. 2m is pretty dead around here, so decided not to install anything in the MS. I do have a HT, but I use it more to listen to NWS than anything else :eek:
 
Ahhh, the project's partially completed, and on something of a hold for the moment.

I'm not licensed yet, but I'll report back with my experiences.

As for egress … lawl. My girl pukes all over the spectrum. Okay, maybe not literally; but there's definitely some horrid screeching upon even



If you're curious, here's my half-completed setup:

Those pics are fantastic. If you could describe your antenna mount point in more detail that would be appreciated. Did you notice any interference in the 2m and 70cm bands?
-TechVP
 
As of today, my license has landed in the database! Feel free to drop me a PM if you want my callsign — I'm doing my best to avoid linking my professional identity with ‘the guy who owns that pink-af Tesla’ (especially if I cut somebody off in traffic and get Googled ;)

It's currently lip-mounted along the left-hand side of the frunk, about a foot (?) from the the rear edge (windshield.) I'll take some photos if I remember next time I'm down in the garage.

No interference whatsoever on the 2m repeater I was talking on tonight here in Chicago; I'll set up remote control, take the train a ways away, and try it from my HT when I have some time to investigate.

I wonder how extensive RFI evaluation is preformed? Is there special equipment? I wonder if I could rent the equipment or space, or pay someone else to do the testing … I'm really curious.
 
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I wonder how extensive RFI evaluation is preformed? Is there special equipment? I wonder if I could rent the equipment or space, or pay someone else to do the testing … I'm really curious.
That's a neat setup you've got. Ham radio is cool stuff, though I'm not involved with it myself. Do you get a range hit with that giant windsock on your frunk? :p

I do testing for a company that makes wireless devices, so I might have some insights into your question. If you're wondering if Tesla does received interference testing ... I imagine they do on mission-critical things like the drive inverter but only test other parts for emitted EMI to comply with regulations. This is probably done on subsystems and modules rather than the vehicle itself. There is some special equipment (spectrum analyzers, anechoic RF chambers, TEM cells, etc) used for this type of testing.

The motor doesn't have brushes by the way, so what you're hearing when you accelerate is the frequency the inverter is switching at and/or the frequency of the AC the inverter generates for the motor. Based on my limited knowledge I would guess the switching frequency would be fixed at some relatively high value (somewhere between 5 kHz and 300 kHz is my best guess) and the AC frequency would vary from 0 Hz through some maximum frequency since it's determined by the rotational speed of the motor. The radio you are using must be some AM variant since an FM-based radio shouldn't be affected much, if any, by a bit of nearby noise as long as it's not too close to the same frequency as the signal you are trying to receive.
 
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So, uh. Yes, I can definitely produce ingress interference, reproducibly, on UHF / 2M. (I can literally, reliably, honk the horn by keying up a particular frequency — on a freakin' Baofeng HT, not even my full-power mobile setup.)

Anybody else having that sort of trouble? I freaked out and shut down all my radios until I'm sitting safely outside my apartment complex, and am *not* in the car … I don't want to be sitting in it if I run across the frequency that closes the HV drive contacts at the wrong moment or something :p
 
So, uh. Yes, I can definitely produce ingress interference, reproducibly, on UHF / 2M. ...
That is disturbing for sure. I would be tempted to contact Tesla (I know they're not great at communication, but maybe this time ...) and say you have a such-and-such transmitter transmitting on a frequency between 144 and 146 MHz and did X, Y, and Z and had N result, make it sound sufficiently technical, and hopefully get in touch with an engineer who can tell you whether or not you should have a radio on the car!
 
But the Baofeng's are notoriously dirty transmitters, so who knows what it's blasting out!
This is a fun thread! Forgive me for barging in again, but there are ways to find out. I used this at my technical college:
IFR-Aeroflex-1200S-Communications-Monitor-Avionics-Tester.jpg


It's designed to allow the operator to perform a thorough set of tests on AM/FM CB-style radios. I'm sure my instructors would have welcomed the opportunity to show the students something different from the twenty well-used AM CBs they had for labs. Perhaps a technical college near you would offer a similar program and would seize the opportunity for a teaching moment? A program that's electronics technologist-related or avionics-related would be most likely to include radio instruction.

Might be handy to have around for ham setups in general ... these ancient units go for $3k-ish these days but still work fine. I believe the instructors told us an equivalent piece of kit would cost $20k new -- of course the new ones do a lot of the knob-twisting and button-pushing for you, but basic functionality is equivalent. It's a spectrum analyzer, AM/FM demodulator, RF signal and tone generator, power meter, and more.
 
That is disturbing for sure. I would be tempted to contact Tesla (I know they're not great at communication, but maybe this time ...) and say you have a such-and-such transmitter transmitting on a frequency between 144 and 146 MHz and did X, Y, and Z and had N result, make it sound sufficiently technical, and hopefully get in touch with an engineer who can tell you whether or not you should have a radio on the car!

Well, first off, I'm no true infosec'er; disclosure is really not my ballgame; second, I'm way too terrified to continue experimenting with it right this second, especially illegally (off the HAM bands, intentionally causing interference, etceteras), not until I have more experience and know precisely what I'm doing; and finally, even if I did wish to disclose, and did wish to / was capable of investigating that particular interference in detail … I'd really not like to register myself with Tesla themselves as That Dude With A High-Power Radio, so that if I ever make any sort of warranty request in the future, or get involved with a crash that's clearly due to Autopilot and has nothing whatseover to do with my transmitter, I find myself getting told “It's your own fault, aftermarket modifications, RFI generation!!!1!” — you know?

This is a fun thread! Forgive me for barging in again, but there are ways to find out. I used this at my technical college:
IFR-Aeroflex-1200S-Communications-Monitor-Avionics-Tester.jpg


It's designed to allow the operator to perform a thorough set of tests on AM/FM CB-style radios. I'm sure my instructors would have welcomed the opportunity to show the students something different from the twenty well-used AM CBs they had for labs. Perhaps a technical college near you would offer a similar program and would seize the opportunity for a teaching moment? A program that's electronics technologist-related or avionics-related would be most likely to include radio instruction.

Might be handy to have around for ham setups in general ... these ancient units go for $3k-ish these days but still work fine. I believe the instructors told us an equivalent piece of kit would cost $20k new -- of course the new ones do a lot of the knob-twisting and button-pushing for you, but basic functionality is equivalent. It's a spectrum analyzer, AM/FM demodulator, RF signal and tone generator, power meter, and more.

Yeah, I've got a full set of kit sitting around (long story), half of which I barely know how to use — a modern/featureful and high-sampling-rate, but nonetheless cheap-o, oscilloscope (I love today's manufacturing technology.); a much nicer, but older, spectrum analyzer; and at least part-time access to an ancient cellular service monitor, which I hear can be twisted to excellent use on HAM equipment … though I've yet to try anything like that.

I wonder if there's a class at the nearby Illinois Tech campus like that …
 
That's a neat setup you've got. Ham radio is cool stuff, though I'm not involved with it myself. Do you get a range hit with that giant windsock on your frunk? :p

I do testing for a company that makes wireless devices, so I might have some insights into your question. If you're wondering if Tesla does received interference testing ... I imagine they do on mission-critical things like the drive inverter but only test other parts for emitted EMI to comply with regulations. This is probably done on subsystems and modules rather than the vehicle itself. There is some special equipment (spectrum analyzers, anechoic RF chambers, TEM cells, etc) used for this type of testing.

Would like to know if you see a measurable performance hit?

In the early 2000's I ran our mfg's computer gear through FCC Commercial Equipment certification. And now that you mention it, we had to take the EUT (Equipment under test) fully connected and configured in exactly the way it will be sold. Every connector - in this case the charge port -- would have to be connected to a charger, and operating / charging from this accessory, to have a valid RF test pass. Yes, separate tests can validate parts and pieces, but in order to obtain the final FCC compliance certificate, it requires a full RF emissions test to the EUT; which is done inside faraday cage.
I add that I'm not aware how automotive would be different than any other electrical -plug-in- appliance.
At the very least, I would expect the tests were run and a certifying body would have filed it with the FCC.
Who knows, some sleuthing through the FCC database just might pull up the FCC documents Tesla filed.

Those with more info, feel free to chime in.
 
Well
Would like to know if you see a measurable performance hit?

In the early 2000's I ran our mfg's computer gear through FCC Commercial Equipment certification. And now that you mention it, we had to take the EUT (Equipment under test) fully connected and configured in exactly the way it will be sold. Every connector - in this case the charge port -- would have to be connected to a charger, and operating / charging from this accessory, to have a valid RF test pass. Yes, separate tests can validate parts and pieces, but in order to obtain the final FCC compliance certificate, it requires a full RF emissions test to the EUT; which is done inside faraday cage.
I add that I'm not aware how automotive would be different than any other electrical -plug-in- appliance.
At the very least, I would expect the tests were run and a certifying body would have filed it with the FCC.
Who knows, some sleuthing through the FCC database just might pull up the FCC documents Tesla filed.

Those with more info, feel free to chime in.

Well, I can't find a database of EMI tests; but I *did* read through Tesla's FCC registrations!
  • WPHD358 on 896–901 / 935–940 MHz (for security / shipping, afaict),
  • KQL352 operating a non-trunked commercial system somewhere specific in the 450–470 MHz band (someone want to go over near the factory and scan? RadioReference has nothing. :p),
  • WNVN467, for unspecified uses in the 902–928 MHz range; I suspect for some vehicle-transponder / telemetrics uses? (Tracking vehicles through production, or testing, or something? This band is usually used for open-road tolling, railroad AEI, etc.)
  • WQOC994 for, I quote, “Support of vehicle research and development activities” — presumably on the same industrial bands (25–50 MHz, 72–76 MHz, 150–174 MHz, 216–220 MHz, 406–413 / 421–430 / 450–512 MHz)
  • WQUU320, ‘engaged in the business of manufacturing parts for vehicles’, and
  • WQUU480, to be used “to coordinate various business activities” (it notes that ‘applicant operates a manufacturing facility.’)
(Also fun: their License Ownership Disclosure mentions the “Elon Musk Revocable Trust” and the U.S. Department of Energy :p)
 
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Hoping someday soon to add a DStar ID 5100A to my rig when delivered. The radio is sitting in the garage waiting for the X to show up.

I found a $$ Larsen Glass Mount antenna -- but wonder what you think about attaching it to the glass atop one of the FWDoors?
If that's problematic, is there room on the oversized front windshield to mount it?
And then there's the other question of any coatings that would interfere w/ the transmission on the glass. If you have input or thought, that would be really helpful.