I got a T99W175 (specifically T99W175.04) to test with my hAP ac2 as it has potential of solving a different problem of mine.
I prepared it for USB 2.0 operation as described here - I attached a 4.7k 0603 (metric) resistor between the left two pads on the back (a bit too big but I didn’t have 0402 ones on hand), removed the second pin from the left on the front, and set AT^CUSTOMER to 0 (originally it was 6, but it showed a “modem failed” error with that setting).
However, it works fine only when not under a higher load. If I try to do a speed test, the modem turns off shortly after starting the speed test.
Does it not have enough power? Should I use a lower value resistor or a short (I’m not sure if it provides power to anything or just pulls something high/low)?
According to T99W175 documentation, it can pull max. 2.5 A (1.8 A typical), while hAP ac2 can only provide max. 1 A on the USB port. Because of that, I also tried to set the maximum transmit power to 0 dBm on all bands using the following script, after doing that it sometimes manages to finish the speed test, but sometimes shuts down anyway (big improvement to download speed - 170 Mbit/s vs 50 on LTE, but upload speed still about the same as on LTE - 28 Mbit/s. I’m not sure if it’s because of the low TX power or something else, but in my case the upgrade would only make sense if both reached 100 Mbit/s).
:local txPower 0;
:for mMode from=1 to=3 do={
:local mBands ([/interface lte at-chat lte1 input="AT^SMTP=$mMode" as-value]->"output");
:local currPos 0;
:while ([:find $mBands "Band" $currPos]) do={
:set currPos [:find $mBands "Band" $currPos];
:local mBand [:pick $mBands ($currPos + 4) [:find $mBands ":" $currPos]];
/interface lte at-chat lte1 input="AT^SMTP=$mMode,$mBand,$txPower"
:set currPos [:find $mBands ":" $currPos];
}
}