I have a couple LHG-LTE version 4 units that are working great with a T-Mobile SIM card. These units are about 3 miles from the tower and can get around 70Mbps download speed. I recently purchased an LHG LTE6 unit to test since the version 4 is being discontinued. I setup the LTE6 just like the version 4 and it works but is not consistent. It drops a lot and the speeds aren't as good as I get with the v4. Does anyone know why I'd have this issue with the newer version 6? Are there other settings that need to be defined? I did set the TTL to 65 just like I do in the v4 unit. I even tried 64 and 66 but its still not stable. Thanks.

Well, you might want to look at the bands being used. Don't know if this US T-Mobile, but if you were using US version of LHG LTE, the older unit have band 4 and Band 5. I'm guessing the newer LTE6 is using Band 12, while older one may been using Band 4.... (and Band 66 likely need to get more speed from 1700Mhz since that's the extended band of Band 4)

For reference,

LHG LTE6
1 (2100MHz) / 2 (1900MHz) / 3 (1800MHz) / 7 (2600MHz) / 8 (900 MHz) / 20 (800MHz) / 5 (850MHz) / 12 (700MHz) / 17 (700MHz) / 25 (1900MHz) / 26 (850MHz)

LHG LTE
1 (2100MHz) / 2 (1900MHz) / 3 (1800MHz) / 7 (2600MHz) / 8 (900 MHz) / 20 (800MHz)

LHG LTE US
2 (1900MHz) / 4 (1700MHz) / 5 (850MHz) / 12 (700MHz)

T-Mobile US Bands...
2 (1900 MHz) / 4 (1700/2100 MHz) / 5 (850 MHz) / 12 (700 MHz) / 66 (Band 4+) / 71 (600 MHz)

I should have mentioned that I am using the US versions of both LHG units. I will dig into the bands a bit and respond with findings. It may take me a few days.

I should have mentioned that I am using the US versions of both LHG units. I will dig into the bands a bit and respond with findings. It may take me a few days.

Well... only the US models have issues with newer modems having less bands... so easy to guess .

But I do suspect you'll see old one using Band 4 and new one using Band 12.

If both are using Band 12, then IDK why one be slower... I think T-Mobile has more Band 66 (the extended part of the Band 12, which none of the LHGs support) and that Band 12 is typically only 5Mhz or 10Mhz channels with T-Mobile...

Do you know how I can verify which bands are being used? Also, would the non-US versions work better? I'm assuming they wouldn't work at all but your comment makes me wonder.

From winbox/webfig, the selected band (and tower info, signal, etc) should show on the lte1 interface under status tab.

No outdoor directional antennas work in US other than the LTE6 ones today. The newer ATL does not work. There is slightly better modem in the US-based Chateau, but that's an indoor unit. See viewtopic.php?t=199087&hilit=band+66

Separately, you can look at cellmapper.net to check band in your area too have some idea what bands are even available – this helps picking what modem work best.