WE826-T2 GoldenOrb/EM7565 Band Lock?

[thejohnfist]

Starting this thread at the request of Mr. Jim Helms.

I'm looking to learn how to lock bands out on a EM7565 inside a WE826-T2 router using GoldenOrb_2018-11-03 ( OpenWrt 18.06.1

I had picked up a M.2 to USB adapter but I'll feel better if there's a reliable way to modify the bands via the browser interface.

Also - I'm using AT&T bands, looking to play around with them a bit. I think band 30 is causing me latency issues. I'm often connected to band 5, 2, and 30. Sometimes it's 5, 2, and 12. Seems significantly better latency wise when that's the combination.

Thanks for any advice!

[thejohnfist]

Forgot to include this if it's useful.

ATTbands91619.jpg

[JimHelms]

The first item I notice is the disparity between the signals being received on the MAIN and AUX of the modem:

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PCC RxM RSRP: -86
PCC RxD RSRP: -100

The PCC is the primary carrier being used (Band 5 in your example).
The SCC1 & SCC2 are the secondary carriers that are being used for Carrier Aggregation (Band 30 and Band 2)

The RxM corresponds to the MAIN connector port on the EM7565
The RxD corresponds to the AUX (Diversity) connector port on the EM7565.

We would like to see the RxM and RxD readings closer to one another--preferably within a few dBm's of each other. Some of the factors that can contribute to this disparity are:

• If using omni antennas that are mounted directly on the router, the placement of the router may need to be twisted or relocated to another area. It is possible that that one antennas (RxD) is not receiving an adequate signal due to interference or obstructions. This will also contribute to the RSRQ of -11.6 db. Ideally, we would like to see this reading above (greater than) -9db.

• It is possible that pigtail connector is loose, at the location where it connects (screws) to the SMA Female bulkhead connector that extends through the router case for the LTE Antennas.

• If using external antennas, be sure the connectors are tight and that all outdoor connections are be properly sealed and weatherized. Moisture in one of the connectors can cause this behavior.

• A loose or damaged MHF4 connector on the pigtail connecting to the modem can also cause this behavior, though this may be somewhat discounted since the secondary carriers' RxD and RxM are close to one another.

You may also notice that your Primary carrier is camped out on Band 5 (at 850HMz frequency) and receiving 5HMz of bandwidth while Band 30 and Band 2 are providing 10HMz of bandwidth.

It is possible that Band 5 is your culprit as opposed to Band 30.

A modem will generally lock onto the strongest (not necessary the fastest) band which is often in the lower frequency spectrum. This is because the lower the frequency (i.e., 700, 850...), the larger the wave length, and the higher its penetration and power--especially over distances and through foliage.

On the other side, the higher the frequency, the shorter its wave length, the greater its absorption and the more difficult its penetration.

In any case, you can create a group of bands that excludes any band you feel is giving issues.

You will first need to download the updated Excel Spreadsheet to identify and assign the bands.

In this example, we will use Band 2, 4, 5 to create a group using those bands which is named: ATT 2,4,5

ATT 2,4,5.png

Next, we will need to identify and assign the individual bands, and program them into the EM7565 using the AT-Command Terminal.

Login to the router, go to MODEM > MISCELLANEOUS > AT-COMMAND TERMINAL and assign each of our bands (running each of the AT Commands, waiting for a response before running the next one):

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AT!ENTERCND="A710"
AT!BAND=10,"B2",0,0000000000000002
AT!BAND=11,"B4",0,0000000000000008
AT!BAND=12,"B5",0,0000000000000010

Next, we will create the group of these bands we named as ATT2,4,5:

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AT!BAND=0F,"ATT 2,4,5",0,000000000000001A

Next, we instruct the EM7565 to use our group for its connection:

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AT!BAND=0F

Next, we will reboot the modem:

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AT!RESET

To consolidate these commands:

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AT!ENTERCND="A710"
AT!BAND=10,"B2",0,0000000000000002
AT!BAND=11,"B4",0,0000000000000008
AT!BAND=12,"B5",0,0000000000000010
AT!BAND=0F,"ATT 2,4,5",0,000000000000001A
AT!BAND=0F
AT!RESET

Once the modem reboots, it should be locked to the group.

[thejohnfist]

Thank you very much for the useful info, I'll work on getting this done this evening.

I'll have to recheck my connections as well, I think they're tight but who knows. Both are roof mounted Yagi style, and the cables had weatherproofing o-rings so hopefully no issues up on the roof.

I only suspect Band 30 because when it sometimes subs out 30 for 12, the latency is remarkably more stable.

[JimHelms]

I'll have to recheck my connections as well, I think they're tight but who knows. Both are roof mounted Yagi style, and the cables had weatherproofing o-rings so hopefully no issues up on the roof.

It is always a good idea to use dielectric grease on the threads of all outdoor connectors, and then seal them with some type of Silicone tape. This will assure no moisture can enter the connectors.

Grease and Sealer.jpg

[thejohnfist]

Okay - I think I have some dialectric grease for spark plugs laying around (Ford Triton issues!) Only tape I have handy is standard black electrical. Might have to do for now.

[swwifty]

The discrepancy between RxM and RxD is most likely a bug in the EM7565 firmware. I've seen this before first hand with the EM7565 on Verizon and AT&T connections.

You can see this because the other carriers don't have such a big difference. That being said, it could also be a real issue, but I doubt it because often when I see big differences between signals and antennas it's due to multipathing. I spent way too much time checking connections for water and re-doing them, etc, etc, to only learn later that the issue was multipath.

You can test this easily by simply moving the antenna with the weaker signal a foot or two (sometimes only a few inches) If it makes a massive difference (like 10dBM) then its multipathing.

[thejohnfist]

Managed to get this working reasonably. For some reason Band 12 will not establish connection anymore. I've only noticed it connected once or twice, and always dropping in favor of 30.

With 30 removed, my latency remains in the 70-110 range, largely staying around 80. Down speeds dropped from approx 100mbps to around 55mbps. No biggie, can always add 30 back if I need the extra boost.

[BillA]

Does anyone know how to disable roaming on the MC7455, or any other Sierras?
The only reference I could find in the AT command manual, is AT!IDSROAM to disable the DM/FOTA roaming, but that's only used for firmware upgrades. Simply locking bands doesn't prevent the modem to roam onto other networks in the absence of signal on the main carrier.
I have found a command in an older Sierra manual to disable roaming, but not sure if this would work on the MC7455 to disable roaming:

AT^SYSCONFIG=2,0,0,2

Quectel modems have a well documented command:
AT+QCFG="roamservice",<x>,1
1 - Disable roaming
2 - Enable roaming
255 - Auto roaming


Also, what's the easiest way to disable IPv6, either in the modem or the router (latest GoldenOrb/WiFix)?
I do know about a custom firewall script, any other methods through a menu?
Any tips would be appreciated.

[JimHelms]

Might look at the AT!NVPLMN command. May be able to use it to lock on a specific MNC

[BillA]

Might look at the AT!NVPLMN command. May be able to use it to lock on a specific MNC

Thanks, will check out NVPLMN if the SYSCONFIG doesn't work, though I don't need to lock it to a specific MCC/MNC especially if different sim cards are used, as long as it doesn't roam onto another carrier. Guess in the end both methods should prevent roaming. Someone got their service deactivated specifically due to roaming onto another network. :/