Unable to acquire GPS lock through metallic windscreen

cynix

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I've just finished installing the F750 on my car. Unfortunately it has a metallic windscreen and the F750 cannot get any GPS signal. Is there any way of hooking up some kind of GPS antenna to the F750, so that I can attach the antenna to a different part of the car that does allow signals through (e.g. rear window)?
 
does it have an external antenna connector?
No, I don't see a connector on the F750. I'm willing to open it up and solder a connector on to it, but I don't know where to start.
 
before you do that does it work outside the car?

I have a heated front window and it works fine with that
 
before you do that does it work outside the car?
Good point. I'll try that.

I have a heated front window and it works fine with that
My car's windscreen is notorious for blocking signals. Other owners have reported trouble with highway toll tags, handheld GPS devices, radar detectors, etc.
 
My car's windscreen is notorious for blocking signals. Other owners have reported trouble with highway toll tags, handheld GPS devices, radar detectors, etc.

check your owners manual, cars with athermic windscreens generally have somewhere on the screen that is transparent to the signal, may or may not suit what you're using but at least will indicate what options you might have
 
check your owners manual, cars with athermic windscreens generally have somewhere on the screen that is transparent to the signal, may or may not suit what you're using but at least will indicate what options you might have
Unfortunately there's nothing in the owner's manual about this. However the manufacturer has suggested a location I could try, so I'll try that soon. Now I just hope I can master the art of using dental floss to remove the existing mount…
 
I tried the manufacturer's suggested location (top edge of windscreen next to rear view mirror), waited 5 minutes (then my arm got sore...), but still could not get a GPS fix. Maybe it needed more time?
 
try it outside the car, how long to get a fix?
It only took about a minute outside the car for it to get a fix.

The good news is, once it gets a fix, I can place it back on the windscreen and it is able to maintain it! 🙂

The bad news is, my car is parked underground, so it'll lose GPS again the next time I drive it. I hope it can remember some satellite information so it can get a fix without being outside the car again. I don't want to keep taking it off the holder/reconnecting the cables every day, I fear that the connectors will wear out quickly.
 
I think most GPS systems revert to a cold start after 12-24 hours with no updates. You may have to install a GPS repeater to allow it to get a lock reliably through the windshield. Just be sure to keep the receiver and transmitter as far apart as possible to minimize the feedback loop.

These are just a couple of examples:
https://www.ebay.com/itm/231587151072https://www.ebay.com/itm/151382219902
KuoH

The bad news is, my car is parked underground, so it'll lose GPS again the next time I drive it. I hope it can remember some satellite information so it can get a fix without being outside the car again. I don't want to keep taking it off the holder/reconnecting the cables every day, I fear that the connectors will wear out quickly.
 
Is the 'metallic' part a coating, or is it between the layers of glass? The owner's manual or dealer should have that answer and know whether you can alter it safely if it's a coating. With today's cars, anything aftermarket and electronic is a gamble and you have to do your research to discover if your intentions will work. Many of my fellow Ham Radio friends have discovered that they can't use their radio in their new cars, especially electric and hybrid-electric models. Sometimes there's a work-around for specific models or problems but often you just have to live with it.

Phil
 
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