Slower speeds on 3926 than R850

[shiver_delight]

Hello, I recently bought and set up my 3926 with a wireless sierra modem
(with pcsforpeople). My question is what I can do about my speeds, as I've
actually had much lower speeds on average now that before with my R850
(though higher uploads). I'm averaging about 5 Mbps down and 7 up,
previously I'd hit 12 Mbps down and 3 up. Sometimes I'm as low as 3Mbps
down.
Curiously, I also use sprint for my phone and using LTE have speeds in the
same range my R850 used to bring in.

I've moved my the modem around my room and looked into locking bands and
after some testing realized that with the stock antennas and my location
that would not work (band 25 is my best bet).
Are there any settings I could tweak to change my speeds? I am not sure I
want to buy outside antennas now as I rent a room and I don't think that
would be feasible.
I've attached the stats of my modem in the best location I've found for it.
Thanks for any replies.

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!GSTATUS: 
Current Time:  3855		Temperature: 52
Reset Counter: 2		Mode:        ONLINE         
System mode:   LTE        	PS state:    Attached     
LTE band:      B25    		LTE bw:      10 MHz  
LTE Rx chan:   8290		LTE Tx chan: 26290
LTE CA state:  NOT ASSIGNED
EMM state:     Registered     	Normal Service 
RRC state:     RRC Connected  
IMS reg state: No Srv  		

PCC RxM RSSI:  -77		RSRP (dBm):  -108
PCC RxD RSSI:  -97		RSRP (dBm):  -140
Tx Power:      0		TAC:         0218 (536)
RSRQ (dB):     -11.2		Cell ID:     00439A12 (4430354)
SINR (dB):     10.8

[JimHelms]

On thing that stands out right away is the disparity in your signal readings.

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PCC RxM RSSI:  -77		RSRP (dBm):  -108
PCC RxD RSSI:  -97		RSRP (dBm):  -140

The RXM is your Main antenna on the MC7455
The RxD is the AUX antenna on the MC7455.

Assuming you have the 4g LTE Antennas on the correct antenna connectors (i.e., do not have a WiFi antenna on it), then:

I would check the U.FL antenna connectors to make sure they are making a good tight connection on the modem, and that the connector is not twisted so that the metal part of the connector is grounding against the metal portion of the modem.

I would also remove the lock washers on the bulkhead antenna connector on the outside of the router case, and tighten the nut back down. This will assure the center pin on the antenna connector is making a good connection.

After you have made these adjustments, try it again. If there is no improvements (closing the signal gaps between RxM and RxD), I would swap the 4G LTE Antennas with one another, and test again. This should tell if one of the antennas might be band.

[shiver_delight]

Thanks for your reply. I am getting similar readings after swapping the antennas and removing the washer; the disparity is the same and the main band is getting lower readings.

I am not sure exactly what you mean about making sure the connector is "not twisted so that the metal part of it is not grounding against the metal part of the modem"? I made sure the nut is really tight and that the antenna was tight as far at it would go. Should I open up the case and look inside for this?

[JimHelms]

I am not sure exactly what you mean about making sure the connector is "not twisted so that the metal part of it is not grounding against the metal part of the modem"?

The MC7455 has three U.FL antenna connector ports: MAIN, AUX, GPS.

The 4G LTE antennas connect to the Main and Aux antenna ports via pigtail cables with U.FL connectors.

Make sure the U.FL connectors are not twisted (rotated) on the modem in such a direction that the metal part of the U.FL connector may be touching the metal part of the modem.

[shiver_delight]

Ok so I took it apart and I think i see what the problem is. One of the 4g pigtail cables is almost completely torn. I am not sure when this happened, is the the one i should buy to replace it? https://thewirelesshaven.com/shop/cables/pigtail- ... 3-pigtail/

[JimHelms]

If that is the 4G LTE pigtail wire that is broke, you will need this U.FL to SMA Female Bulkhead Pigtial as a replacement.

Looks like it got between the two parts of the case (and right over the screw hole boss) when reassembled. Once must take caution when putting the two parts of the case back together that the wires are twisted and out of the way.

[shiver_delight]

Ok so I replaced the wire, everything seemed to be working and I was getting internet access. I then proceeded close the case and now I don't get internet at all. I am not sure what happened, here is my GSTATUS:

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Current Time:  165		Temperature: 40
Reset Counter: 1		Mode:        ONLINE         
System mode:   LTE        	PS state:    Not attached 
LTE band:      B26    		LTE bw:      5 MHz   
LTE Rx chan:   8763		LTE Tx chan: 4294967295
LTE CA state:  NOT ASSIGNED
EMM state:     Deregistered   	Limited Service
RRC state:     RRC Idle       
IMS reg state: No Srv  		

PCC RxM RSSI:  -71		RSRP (dBm):  -93
PCC RxD RSSI:  -67		RSRP (dBm):  -88
Tx Power:      0		TAC:         0218 (536)
RSRQ (dB):     -6.8		Cell ID:     00439A1A (4430362)
SINR (dB):     10.8

[shiver_delight]

Ok finally i got it to work after reinserting the sim a hundred times. I don't know what the issue was but I think I will just leave the router as is and not put the case on.

Speeds a little higher now (5.4 Mbps down) but still not even where the R850 was.

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PCC RxM RSSI:  -73		RSRP (dBm):  -103
PCC RxD RSSI:  -80		RSRP (dBm):  -111
Tx Power:      22		TAC:         0218 (536)
RSRQ (dB):     -9.6		Cell ID:     00439A12 (4430354)
SINR (dB):     10.8

[shiver_delight]

Sometimes I'll test the speed on the 3926 and it will be as low as 1.5 Mbps while at the same time my sprint phone will be 10 times higher.

At this rate I'm thinking of returning at least the wireless card and just buying a R850. I know i won't be able to return the 3926 since i had to replace the cable.

[JimHelms]

Ok finally i got it to work after reinserting the sim a hundred times. I don't know what the issue was but I think I will just leave the router as is and not put the case on.

Speeds a little higher now (5.4 Mbps down) but still not even where the R850 was.

You did replace the U.FL to SMA pigtail connector with a SMA and not a RP-SMA. They look similar but are different.

Can you receive band 41 at your location?

Have you checked your hotspot to see what band is it using?

Also, you may try putting the SIM into the hotspot and update the user profile and PRL. Then, retry the SIM card in the router.

Post all of your GSTATUS? stats

[shiver_delight]

This is the cable i bought, I'm 99% sure it is the right one. https://www.amazon.com/gp/product/B071H ... UTF8&psc=1
(I bought it on amazon cause i wanted to get it quicker)
Now both antennas get pretty much exactly the same signal.

I tried changing the bands before when I didn't know one of the cables was faulty, may try again now. Before it didn't even connect to anything other than band 25 (what I'm currently on).
I also updated the prl and profile less than 2 weeks ago.

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Full GSTATUS:
Current Time:  13829		Temperature: 47
Reset Counter: 1		Mode:        ONLINE         
System mode:   LTE        	PS state:    Attached     
LTE band:      B25    		LTE bw:      10 MHz  
LTE Rx chan:   8290		LTE Tx chan: 26290
LTE CA state:  NOT ASSIGNED
EMM state:     Registered     	Normal Service 
RRC state:     RRC Connected  
IMS reg state: No Srv  		

PCC RxM RSSI:  -85		RSRP (dBm):  -106
PCC RxD RSSI:  -87		RSRP (dBm):  -107
Tx Power:      0		TAC:         0218 (536)
RSRQ (dB):     -7.4		Cell ID:     00439A12 (4430354)
SINR (dB):      8.8

[shiver_delight]

I have tried locking into band 41 again and have not had any success connecting. Any last steps I should try?
I've also recently raised the router as high as possible in my room and have noticed that the download speed doesn't increase much, but the upload can jump to as high as 17 mbps, which is very interesting as i couldn't even get a 1/4 of that before?

[bjames]

I have tried locking into band 41 again and have not had any success connecting. Any last steps I should try?
I've also recently raised the router as high as possible in my room and have noticed that the download speed doesn't increase much, but the upload can jump to as high as 17 mbps, which is very interesting as i couldn't even get a 1/4 of that before?

Usually, the higher the router (or at least the antennas), the stronger the carrier signal and the lesser the interference. Likewise, placing the router in a different room can often result in substantial signal gains or losses. This also hints the need for external antennas.

As for Band 41, have you confirmed that it is available at your location?

Curious to see the difference in the GStatus in the higher and lower location.

[shiver_delight]

Usually, the higher the router (or at least the antennas), the stronger the carrier signal and the lesser the interference. Likewise, placing the router in a different room can often result in substantial signal gains or losses. This also hints the need for external antennas.

As for Band 41, have you confirmed that it is available at your location?

Curious to see the difference in the GStatus in the higher and lower location.

I know there is a band 41 about 6 miles away, but I guess i can't hit it without upgrading my antennas. I am currently a college student and renting a room on campus, so I am not sure I really want to put up antennas, especially since I may be moving out in 4 months or so.
Ideally I would like to just get to the point where my R850 was before it crapped out. I was getting around 10-12 Mbps down.

Here is the updated gstatus:

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GSTATUS: 
Current Time:  23448		Temperature: 54
Reset Counter: 1		Mode:        ONLINE         
System mode:   LTE        	PS state:    Attached     
LTE band:      B25    		LTE bw:      5 MHz   
LTE Rx chan:   8665		LTE Tx chan: 26665
LTE CA state:  NOT ASSIGNED
EMM state:     Registered     	Normal Service 
RRC state:     RRC Connected  
IMS reg state: No Srv  		

PCC RxM RSSI:  -77		RSRP (dBm):  -101
PCC RxD RSSI:  -72		RSRP (dBm):  -100
Tx Power:      0		TAC:         0218 (536)
RSRQ (dB):     -10.5		Cell ID:     00439A02 (4430338)
SINR (dB):     16.2

[shiver_delight]

Just realized, it looks like I'm hitting a different tower now? The band is the same but the bw is 5Mhz instead of 10Mhz and the cell id is different.

[JimHelms]

Yes, also know that a lot of Sprint users have been experiencing issues in different locations for the past month or two due to network hardware and software upgrades.

Three weeks ago I had a WE826 with good signals but terrible service. Drove to two different towers on the lake and it worked great. But the tower I was connecting to at the marina, was all but dead. It remained unusable for the three days I spent there. This past weekend it was back to normal.

If might be worth checking [urlhttps://www.sprint.net/maint_view.php]HERE [/url]to see if your location is on the list.

[JimHelms]

If your still having issues you many want to try this updated firmware.

I do not know if it will help your particular problem but it may not hurt to try.

It does contain a number of modem fixes for the Sierra and Quectel modems as well as a few other fixes.

[shiver_delight]

Something happened today that caused me to lose internet completely. I have checked the link, there is no work being done on towers near me, and I do have the newest firmware (assuming it is the one from late august).

Here is my current GSTATUS:

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Current Time:  2745		Temperature: 34
Reset Counter: 1		Mode:        ONLINE         
System mode:   LTE        	PS state:    Not attached 
LTE band:      B25    		LTE bw:      10 MHz  
LTE Rx chan:   8290		LTE Tx chan: 4294967295
LTE CA state:  NOT ASSIGNED
EMM state:     Deregistered   	Limited Service
RRC state:     RRC Idle       
IMS reg state: No Srv  		

PCC RxM RSSI:  -67		RSRP (dBm):  -96
PCC RxD RSSI:  -68		RSRP (dBm):  -98
Tx Power:      0		TAC:         0218 (536)
RSRQ (dB):     -11.0		Cell ID:     00439A12 (4430354)
SINR (dB):     11.2

I think the problem is the EMM state being deregistered? Thanks for any help.

[shiver_delight]

Fixed the problem from yesterday but I'm having more problems with my 3926 leading to no internet, this time it's not because it's not reading the simcard (AT+CPIN? command says ready).

Here's my GSTATUS:

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Current Time: 71140 Temperature: 36
Reset Counter: 1 Mode: ONLINE 
System mode: LTE PS state: Not attached 
LTE band: B25 LTE bw: 20 MHz 
LTE Rx chan: 8140 LTE Tx chan: 4294967295
LTE CA state: NOT ASSIGNED
EMM state: Deregistered Attach Needed 
RRC state: RRC Idle 
IMS reg state: No Srv

PCC RxM RSSI: -72 RSRP (dBm): -106
PCC RxD RSSI: -75 RSRP (dBm): -108
Tx Power: 0 TAC: 0413 (1043)
RSRQ (dB): -13.8 Cell ID: 00EEC70A (15648522)
SINR (dB): 13.2

Thanks for any help.

[JimHelms]

Just out of curiosity, run the follow command:

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AT+CFUN?

While the modem is in the same state as you posted above.

Also run:

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AT!PCINFO?

[shiver_delight]

It says the follow, i assume it's good since 1 usually means good?

AT+CFUN?
+CFUN: 1

[JimHelms]

Also run:

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AT!PCINFO?

[shiver_delight]

I get the following:

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AT!PCINFO?
State: Online
LPM voters - Temp:0, Volt:0, User:0, W_DISABLE:0, IMSWITCH:0, BIOS:0, LWM2M:0, OMADM:0, FOTA:0
LPM persistence - None

OK

[latic]

I've been having very similar issues to this. Speed sticking at the magical 5mbps mark.

While on the phone today I got the tech to check contention on the tower (I've got a direct sprint account and MC7455 is my provisioned device) and he told me he could see a lot of issues with the tower and would red flag it.

It could be that they've recently done a roll out of firmware thats causing issues on the tower / antenna hardware resulting in this kind of behaviour. I'll get as much info as I can about the fix they put in place (if they do).

We have another device which uses the Sprint Mifi device and this can connect to the same tower without an issue.