DL speed tanked

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DL speed tanked

Post by brcisna » Sun Oct 17, 2021 9:56 am

Hello ALl,

New to cellular internet connectivity with VSBLINTERNET . em7455 SW modem
Someone school me here.

A very stable setup after much wrangling with settings, iptables,etc for the last three weeks.
Have been getting consistently 30-50 mBps down and about 1.5 mBps up.
The router machine is Debian Bullseye and left on overnight and today DL speed is down to 5mBps but upload speed is about 5 mBps. From doing some reading the last couple weeks,depending on the link agregation, the upload/download speeds may be like this. It is almost as a tethered phone connecion now in regards to speeds.

Only thing i go off of what shows in Modem Manager as the 'operator code' which i had always thought is the connected tower? This never changes.
5mBps isn't bad for us,,after having had 1.5 mBps for the last ten years via local wireless ISP.
What would i look for with AT commands for connected towers,etc?

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Re: DL speed tanked

Post by Dr-BroadBand » Wed Oct 20, 2021 9:30 am

Captain obvious here :geek:

It’s either your signal or your SIM or both.

From your screenshot it looks like your signal is a little week.

The easiest way to improve your signal for a test is bring your setup to the tower.

Best to use the vehicle 🚗 12VDC to power your stuff.

I’ve seen power inverters cause noise and lower your Signal quality.

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Re: DL speed tanked

Post by Didneywhorl » Thu Oct 21, 2021 7:46 am

19% signal can wreak havok on any data connection attempt.

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Re: DL speed tanked

Post by packlet » Thu Oct 28, 2021 12:50 am

what sort of antenna(s) connected to your modem, and did they get moved or re-oriented (maybe by strong wind, etc...) how far from tower are you? did someone park a truck in your line of sight in that direction? etc...

If nothing changed at your end, could be something changed at the tower to cause your modem to pick a different band than the one/s getting your higher speeds...

AT command "at!gstatus?" will show a good amount of info on the current connection on the SW modems.
(preferably run under some load to see if CA is kicking in and on which bands...)

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