My Ultimate LTE router using a Raspberry pi 4B

This a discussion place for anything.
poodad
Posts: 30
Joined: Thu Jul 23, 2020 4:09 pm
Has thanked: 1 time
Been thanked: 16 times

Re: My Ultimate LTE router using a Raspberry pi 4B

Post by poodad » Mon Oct 19, 2020 8:21 am


poodad
Posts: 30
Joined: Thu Jul 23, 2020 4:09 pm
Has thanked: 1 time
Been thanked: 16 times

Re: My Ultimate LTE router using a Raspberry pi 4B

Post by poodad » Mon Oct 19, 2020 8:31 am

SliverGT wrote:
Sun Oct 18, 2020 8:27 pm
Nice work, do you have a better picture of how your mast is attached to the roof?
I made the telescoping post from two pieces of metal tubing from Home Depot that fit one inside the other almost perfectly. One was a section of electrical conduit and the other a chain link fence top rail section.

I drilled a 1 1/8" hole in the top of the ridge vent which was exactly the same diameter of the outside pole.

The bottom of the pole rests in a "cup" made from a small bit of 2X4 with a 1 1/8" hole drilled 90% through. This is screwed to the attic floor. I made a locking collar that attaches to this block of wood and when tightened, prevents the pole from rotating.

poodad
Posts: 30
Joined: Thu Jul 23, 2020 4:09 pm
Has thanked: 1 time
Been thanked: 16 times

Re: My Ultimate LTE router using a Raspberry pi 4B

Post by poodad » Mon Oct 19, 2020 8:36 am

R1250GSA wrote:
Sun Oct 18, 2020 3:59 pm
OUTSTANDING!
Well played Dr. Frankenstein.

What are the speeds now that the smoke has settled?
Which carrier?
Any lessons learned from your modem choice, the Sierra CAT-12?

Yes, I would like to see your Perl scripts.
Right now, I'm testing with a business class AT&T SIM using the i2gold APN. Speeds are good (12Mb/3Mb), but latency is terrible at around 1s. I guess I'm hitting AT&T routers on the moon or something.

Learnings:

1. The Raspberry Pi 4 is not ready for prime time as a router. If it weren't for for some guru named Wulfy23 who is building a top-notch community build of OpenWRT for the RPi4, I'd have been stuck. The stock daily snapshots for the RPi4 suck.

2. The EM7565 seems like a top notch LTE modem. I'm seeing a bit of weirdness with AT commands, but everything seems to be working. I'll know more when I start trying band locking.

3. I need to play around with QMI vs MBIM. I've heard rumors the QMI works better for Qualcom based devices.

4. The EM7565 gets HOT when under load. My modem temp shot up to 65 degrees C while testing. It may get a heatsink

5. Grafana is awesome stuff!

R1250GSA
Posts: 90
Joined: Fri Sep 25, 2020 10:45 am
Location: USA
Has thanked: 18 times
Been thanked: 13 times

Re: My Ultimate LTE router using a Raspberry pi 4B

Post by R1250GSA » Mon Oct 19, 2020 9:28 am

I do not see any grounding of your roof setup.
It looks like a very juicy lightning rod.

poodad
Posts: 30
Joined: Thu Jul 23, 2020 4:09 pm
Has thanked: 1 time
Been thanked: 16 times

Re: My Ultimate LTE router using a Raspberry pi 4B

Post by poodad » Mon Oct 19, 2020 7:26 pm

R1250GSA wrote:
Mon Oct 19, 2020 9:28 am
I do not see any grounding of your roof setup.
It looks like a very juicy lightning rod.
I have a couple of VERY tall trees close to the house and the antenna should fall within the cone of protection of those trees. However, I am going to add a ground just to be safe, just haven't done it yet.

poodad
Posts: 30
Joined: Thu Jul 23, 2020 4:09 pm
Has thanked: 1 time
Been thanked: 16 times

Re: My Ultimate LTE router using a Raspberry pi 4B

Post by poodad » Wed Oct 21, 2020 10:27 am

Update: I've been testing some more. When left to defaults, the modem will do carrier aggregation with band 66 and some other band which escapes me at the moment. I do remember that the secondary band was one of the 700-800Mhz bands. This resulted in download speeds of around 16Mb, but upload speeds of only 1Mb. The modem temp went to 65 degrees. Testing using RDP into a terminal server resulted in a not great experience.

I'm about 5 miles from the tower (I think - the cell ID I'm seeing doesn't seem to exist on any of the locator web sites), and I have heavy amounts of trees and a hill obscuring the path. When using CA with B66 as the primary, my RSSI was around -90dB which I'd expect given that B66 is 1.7Ghz.

I tried band locking to the couple of low frequency bands this tower supports, and B5 seemed best. RSSI in the low to mid -70dB range. Downloads dropped to 10Mb, but uploads jumped to 6Mb. Overall experience was better. RDP was markedly better.

Now, I need to find a provider to replace the testing SIM I'm using. Nomad used to be a good choice, but they've recently gotten a terrible reputation of disrupted service and continuing to charge credit cards after canceling. They are expensive now to boot.

Visible seems to be a popular choice, as does the AT&T post paid tablet plan. Both of these require some extra hoops to jump through, but I guess I'll do whatever it takes.

lordrylen
Posts: 5
Joined: Tue May 19, 2020 7:34 am
Location: North East Texas
Has thanked: 2 times
Been thanked: 0

Re: My Ultimate LTE router using a Raspberry pi 4B

Post by lordrylen » Sat Feb 20, 2021 3:32 pm

poodad wrote:
Wed Oct 21, 2020 10:27 am
Update: I've been testing some more. When left to defaults, the modem will do carrier aggregation with band 66 and some other band which escapes me at the moment. I do remember that the secondary band was one of the 700-800Mhz bands. This resulted in download speeds of around 16Mb, but upload speeds of only 1Mb. The modem temp went to 65 degrees. Testing using RDP into a terminal server resulted in a not great experience.

I'm about 5 miles from the tower (I think - the cell ID I'm seeing doesn't seem to exist on any of the locator web sites), and I have heavy amounts of trees and a hill obscuring the path. When using CA with B66 as the primary, my RSSI was around -90dB which I'd expect given that B66 is 1.7Ghz.

I tried band locking to the couple of low frequency bands this tower supports, and B5 seemed best. RSSI in the low to mid -70dB range. Downloads dropped to 10Mb, but uploads jumped to 6Mb. Overall experience was better. RDP was markedly better.

Now, I need to find a provider to replace the testing SIM I'm using. Nomad used to be a good choice, but they've recently gotten a terrible reputation of disrupted service and continuing to charge credit cards after canceling. They are expensive now to boot.

Visible seems to be a popular choice, as does the AT&T post paid tablet plan. Both of these require some extra hoops to jump through, but I guess I'll do whatever it takes.
How do you send AT commands to your modem? I cannot get socat to work properly.

Post Reply