LEM 7 antenna problem?

When I got the watch some weeks ago I tried all the functions and all seemed well with GPS, bluetooth, wifi and GSM. Bluetooth worked OK for at least 2 meters, GPS lock in under 5 seconds from cold boot, and wifi connected normally.

But last week I noticed that if I was walking outside the bluetooth connection was breaking up unless I lifted my arm. And it gradually got worse, now the bluetooth range is <20cm. And GPS lock outside on a open space gets GPS lock in 5-10 minutes and signal strength on the satellites is orange to yellow on app “GPS Test”. GSM still shows full bars on 4G after I uninstalled Universal Launcher which doesn’t allow me to connect on 4G! And UL disabled all notifications, watch did ‘ding’ and shake but no notifications arrived.


Flexing the band on the watch sometimes seems to improve reception on GPS. Does anybody have the same experience? I am going to open the watch and see if the antenna/antennas have got disconnected or something, when I have the time. Anybody done that already? Something I have to think about or any warnings?

The LEM7 has 2 thin film antenna strips which sit in the straps and are connected with a short wire soldered on the strip and plugged on the main board. The antenna in the strap closest to the red button is a combo antenna for gps/bt/wifi as is indicated on the main board and the other one is for the mobile data modem (gsm/2g/3g/4g). I checked this by opening the watch and you can find a few pics in other posts. I can post a pic of the gps/bt/wifi antenna tomorrow.

My main problem with this watch is gps, it takes a long time to get a 3d fix, and when I am walking or biking usually not getting a fix at all. I tried recalibration of gps and added an alu foil between the main board and the battery. It didn’t help much.

Wifi and bt works quite well for me, 4g not so good. Hopefully a future firmware will improve it.

In your case I can imagine that the main board antenna wires connectors came lose or maybe the thin film solder joints are not good.

Here is a pic of the thin film combo antenna (gps/bt/wifi) in the wrist strap

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