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Just saw my earlier posts in this thread. I've actually picked the hoppy back up, mostly digital modes on UHF.
Hi all,
My Larsen on-glass mount on the left rear fixed window of my model S seems adequate for repeaters on 2M/UHF. I also use a 15" sq. piece of steel sheet metal on the rear parcel shelf with mag mounts for 220, 900 and 1.2 GHz (needs a rubber duck for 220), these work well for repeaters.
Andrewket, are you playing with DMR on UHF?
73,
Oliver KB6BA
My Larsen on-glass mount on the left rear fixed window of my model S seems adequate for repeaters on 2M/UHF. I also use a 15" sq. piece of steel sheet metal on the rear parcel shelf with mag mounts for 220, 900 and 1.2 GHz (needs a rubber duck for 220), these work well for repeaters.
Andrewket, are you playing with DMR on UHF?
73,
Oliver KB6BA
VerityZooms
Member
Man, I really need to look into the digital modes — I've done *nothing* but voice yet. #noob
green1
Active Member
Although I have no permanent ham radio mounted, I did put one in this weekend for an event.
I used an FT8900 and put it in the cubby below the 17" screen. Power was from a dedicated 12v 20A circuit that I wired to that location a while back directly from the battery.
For antenna I routed it to the rear hatch, and then to a custom mount that I made to screw in to the rear right roof rack mount.
Worked great.
73 de VE6RAH
I used an FT8900 and put it in the cubby below the 17" screen. Power was from a dedicated 12v 20A circuit that I wired to that location a while back directly from the battery.
For antenna I routed it to the rear hatch, and then to a custom mount that I made to screw in to the rear right roof rack mount.
Worked great.
73 de VE6RAH
I've enjoyed following this thread and the other similar one going on within TMC. Forgive me for going slightly off topic, but I've been thinking a lot about how much current is safe to draw from a direct hookup to the 12V battery (fused of course), for radio purposes. I'm planning on a Motorola DMR mobile installation which can draw up to 15A on high power (which I'll rarely use). Given that the Tesla 12V battery is a bit on the small side, I gather that 15A should still be ok for intermittent draw, taking into account the other 12V loads that the car uses?
Thanks for your info Andrewket, hope to catch you on one of the nationwide DMR channels someday.
73,
Oliver KB6BA
Thanks for your info Andrewket, hope to catch you on one of the nationwide DMR channels someday.
73,
Oliver KB6BA
ThisIsTrue
Re-member
So I guess only the windshield is metalized? That's good to know.
A friend runs an HF rig in his pickup. He uses a screwdriver antenna attached to a tow ball mount, which he installs into his hitch receiver. If anyone is willing to install a hitch on their S, they could use a similar setup.
VerityZooms
Member
I need to figure out how to test this once-and-for-all — I really want to know whether my Model X's rear, and side, windows are metallized or not. ಠ_ಠ
Either devise some sort of low-power, directional, transmitter/receiver pair on the inside and outside; or locate myself a card with a Massachusetts billing-address and pay for access to their service documentation …
hill
high fiber member
Can't speak for the X, but in the S, it's only the front windshield that blocks RF. I installed a GPS repeater, to provide a signal to my dashcam (which is adjacent to the rear-view mirror and signal is blocked by the windshield), in the trunk, and it "sees" the satellites through the hatch window.
hill
high fiber member
LAIRD - meah. antenex definately used to be pretty decent - before Laird bought them out several years ago. Haven't been too impressed since the merger. There's some decent prices on used Antenex stealth models on eBay for VHS UHF every once in a while. Even so ... YEA DRILL BABY... thats how we roll.
Speaking of drilling - here's a shot of the bayonet style custom machined stainless antenna mount that i made for my 10m/160m screwdriver. 2½" hole sawed - right thru the bumper - looks nice & clean
Got a sweet auto tuner for it - that auto adjusts @ 10watts - then watchout! (smirk) .... still - iduno ... i might want to find out from tesla if everything is shielded well enough to handle legal limits. The S arrives in about 2 weeks. One would certainly suspect that's the case. But yea - my favorite toy, the Kenwood 2000 goes all the way up to 1.2ghz. Transmitting above 10m, & although ungainly long & not perfectly matched, nothing beats the diamind SG7900 super gainer dual band . . . it actually does ok on 220 & 6m as well. But for the OP - you might as well forget about a MAG mount. Would you like to borrow a hole saw?
Yes I realize this is a zombie thread, but just one more thing ~
no its not dying. If you gave up a decade ago you probably never heard of the IRLP, micro nodes, alstar etc -
Computers enable smartphones to do everything from SSTV to full duplex communication via the web. It's revitalized the service. Welcome to the 21st century ... better late than never!
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VerityZooms
Member
LAIRD - meah. antenex definately used to be pretty decent - before Laird bought them out several years ago. Haven't been too impressed since the merger. There's some decent prices on used Antenex stealth models on eBay for VHS UHF every once in a while. Even so ... YEA DRILL BABY... thats how we roll.
If you drill a big hole in your Tesla, I'll come slap you.
Okay, maybe not ... each to their own, I suppose. Maybe in a Model III, but I refuse to accept any permanent installation in a $100,000+ car! Yikes. O_O
They declined to provide any specific information when I asked; hence my adventures earler in this thread, experimenting on my own. If you get a more helpful response, please do share! )'=
I'm pretty happy with my Comet UHV-6 at the moment, although I haven't gotten the SWR story pretty quite yet — I might need a no-ground-plane setup to replace it; I'm starting to think the aluminum body is Not A Happy Camper?
Thank you! I'm a brand-new HAM in my late 20's; my father re-certified with me (so we've got sequential callsigns; it's cute af) at 68. I've convinced a few friends to look into it, and plenty of the programmer/electronics-hobbyist types I've talked to seem intrigued.
Dying, nah. Just changing.
Postscript: Ahhhhh, turn off the endless emboldening, it's making my inner typographer cry.
green1
Active Member
The DC-DC converter is rated for 2500 watts. I wouldn't worry. Especially if you really think about it. Your radio likely doesn't draw 15A most dual band mobiles, operating at 50 watts draw under 12A, and most commercial radios top out at about 20 watts, so should draw a fair amount less. Additionally, that's only while actively transmitting, which you are unlikely to sustain for hours on end, your duty-cycle over any measurable amount of time is likely well less than 10%.
Tesla rated their 12V outlet for 15A continuous, so that much is easily safe, and I wouldn't worry about drawing a whole lot more if coming straight from the battery.
VerityZooms
Member
This is precisely the question I'm wrangling with right now, personally. I've got a whole host of equipment being stuffed into this poor car; and I'm really not sure what current-targets to set. What's safe to fuse for? What's safe to draw continuously; what's safe to draw for short periods? At what level, and/or duration, of draw, will I overwhelm Tesla's notoriously tiny lead-acid “not-really-SLI” battery, and presumably cause the DC-DC converter to kick in; and will it generate any additional noise I want to avoid when it does so?
I haven't thought of a way to test these things without damaging my car. Looking more and more like I need to make a Massachusetts friend.
green1
Active Member
The DC-DC converter is always running when the car is "on", so no risk of it "kicking in and generating more noise" the converter cycles on and off as needed when the car is "off". While it's hard to know what the total free capacity of the DC-DC converter is, I'd hazard a guess that it's probably over 1000w (though it may vary a bit if using all 5 seat heaters and the rear defrost!)This is precisely the question I'm wrangling with right now, personally. I've got a whole host of equipment being stuffed into this poor car; and I'm really not sure what current-targets to set. What's safe to fuse for? What's safe to draw continuously; what's safe to draw for short periods? At what level, and/or duration, of draw, will I overwhelm Tesla's notoriously tiny lead-acid “not-really-SLI” battery, and presumably cause the DC-DC converter to kick in; and will it generate any additional noise I want to avoid when it does so?
I haven't thought of a way to test these things without damaging my car. Looking more and more like I need to make a Massachusetts friend.
Honestly, I can't imagine a scenario in amateur radio that I would worry about capacity in this vehicle. And better than any ICE, you have 85kWh of capacity on-tap without starting the engine!
As for capacity to fuse for, etc, that will be based on your gear similarly to any other vehicle or even stationary installation.
This car has more 12V capacity than many standard vehicles, so unless you're running an HF amplifier pushing out a kW or more, I simply wouldn't worry about it.
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