I’ve been struggling with an embedded EM7455 device for several months now and after trying a whole host of options, I’m throwing myself at the mercy of other experts for help. The EM7455 is installed in an embedded edge device (Core i7) that runs Ubuntu 18.04 server. Nothing magical here.
I’ve had terrible upload speeds from this device from the start. No matter what we do the upload speed is ALWAYS 0.26Mbps via speedtest-cli. We initially tried an external antenna, basic omnidirectional antenna mounted to a large metal cabinet with a great ground plane. Results were the same, 0.26Mbps upload.
We tried changing the firmware to generic from the stock Verizon firmware. Same, 0.26Mbps. We ensured that we were using the latest firmware from Sierra Wireless, SWI9X30C_02.33.03.00, no change - 0.26Mbps. We’ve tried different versions of ModemManager, no change. We even thought it might be the device itself so we ordered 2 new EM7455s, also no change.
Most recently we installed a Wilson Wideband 8.5dBi directional antenna and no matter where we aimed it, 0.26Mbps. Download speeds with the Wilson improved a lot - 30Mbps.
Thinking that perhaps we were just in a bad area, though, we tethered the device to a phone on the same network. We were able to get 5/5Mbps via Wifi, tethered. So that told us that it wasn’t some strange network/propagation issue, and that it was actually possible to get decent speeds.
So why is this EM7455 stuck at 0.26Mbps?! Help!