ingenium

Both are phones that Sprint sells themselves, even if it's not that particular "model" (ie S9 running unlocked vs Sprint firmware). iPhones are all the same firmware and is a device that Sprint sells. I see BYOD as typically meaning Android phones that Sprint doesn't sell directly, but that are "supported" in that it's whitelisted for the network and that they often have support documentation for (and it shows with the correct device name on your account). Which I guess is a fairly small subset of phones... Really, it comes down to when Sprint will quit trying to implement it their own way and use the API that every other carrier uses, so that it will work on all phones with capable hardware and FCC certification. It would make it so much easier on Sprint too, since they wouldn't have to make custom software for every phone and get the manufacturer to add it in. Sent from my Pixel 2 XL using Tapatalk

The phone was fine, I just had to power off the old one and then the new one started working as soon as I rebooted it. It's because Sprint doesn't just use the SIM for authentication on the network. Essentially, the old phone was still hanging onto the authorization on the CDMA side, and it had to release it for the new one to get it. They shouldn't hassle you about a new SIM in a case like this. They just might not have the correct one for your phone in stock. So they may have to either order it, or they can maybe pull one from a used/returned phone in the back and put it on your account. Also, double check that the IMEI or ESN that Sprint has on file for your line actually matches your phone. Sent from my Pixel 2 XL using Tapatalk

Sprint might do the same. BYOD devices don't get wifi calling or Calling+. It remains to be seen if they'll push their VoLTE config to AOSP (public Android source code), or publish an app that configures VoLTE (part of the Android API since 6.0 I believe). Google makes it really easy for carriers to enable VoLTE on Android, and push it out to all capable phones instead of having to wait for an OS update. Sent from my Pixel 2 XL using Tapatalk

Changing JUST the band priorities shouldn't have the effect that you're seeing. If you changed other things while in there, then that's another story... Can you get to the dialer with the SIM inserted? You can dial *#*#72786#*#* which will wipe the Sprint config and cause it to fetch it again from the network. You have to so this with a Sprint SIM inserted, and chances are it'll be locked out as soon as invalid SIM comes up, so have it typed out and ready to type the last * right as you enter the SIM. You can also maybe try booting it into safe mode. That might help. I saw a similar issue once when I swapped phones, and reused the SIM, but the original phone wasn't powered off or on airplane mode (just had its SIM removed). It behaved close to what you're seeing, working for a fraction of a second before saying invalid SIM over and over before locking. If there are any other phones that previously were on that line, make sure they're all powered off. If none of these work, ask at the Sprint store if they can replace your SIM. Make sure they give you the correct one for your phone model (they all look the same. There is a spreadsheet on here somewhere with the model number for each phone's SIM). They likely will, but it's not unheard of for the store reps to not know that different phones need different SIMs since most phones already come with a SIM. Sent from my Pixel 2 XL using Tapatalk

That's odd. For any apps? Do you have backups disabled in your preferences? If you open Google Drive on your phone, open the left side menu, go to Backups, select a device, and it should show you all of the applications that are backed up, the last date/time of backup, and the size of the backup (doesn't count towards storage quota). Sent from my Pixel 2 XL using Tapatalk

This works for me, and has for a while. It even restores your database of logged sites. The data is only backed up at night (or while idle at least), while charging (and maybe at 100%?), and on wifi, so if those conditions weren't met since you installed the app and configured your settings, then they likely haven't had a chance to backup yet. That being said, I have heard others say it didn't restore onto a new device. But this sounds like a Google issue rather than a Signal Check issue. Sent from my Pixel 2 XL using Tapatalk

No, neither support UL CA. Sent from my Pixel 2 XL using Tapatalk

Yeah the SNR is pretty bad on the second carrier. I've found that rsrp and SNR are always lower for the non PCC. Usually 5-10 dbm lower. I think because the radio is tuned to the PCC rather than somewhere in the middle, so the SCCs are a bit out of tune (vs having everything slightly out of tune, albeit less so). That might be something that can be improved with modem firmware updates, but is to be expected since you'd want the PCC to have the best signal and allow the SCCs to drop. Sent from my Pixel 2 XL using Tapatalk

Yup. I don't think that FDD upload CA is available on any Qualcomm modems yet. But B41 TDD upload CA is. So presumably that's what this is. Arguably, upload FDD CA isn't that important since it usually has plenty of capacity. TDD is where upload is hindered, so it would be most useful there. Hybrid FDD TDD CA will also really help uploads, assuming that FDD is the PCC. Sent from my Pixel 2 XL using Tapatalk

Hybrid means B25/41 CA. Sent from my Pixel 2 XL using Tapatalk

It looks like 192.0.0.1 - 192.0.0.7 is a set of IPs reserved for DS-LITE: https://mxtoolbox.com/SuperTool.aspx?action=arin%3a192.0.0.4&run=toolpage We need an IPv4 sample from a device using the i.ispsn APN to see if it's assigned an IPv4 address in this range or a different range. It's possible that i.ispsn uses their legacy carrier grade NAT (perhaps with no IPv6 assigned to the device?), and x.ispsn uses DS-LITE. DS-LITE is a way to tunnel IPv4 within IPv6 https://www.juniper.net/documentation/en_US/junos/topics/concept/ipv6-dual-stack-lite-overview.html and https://www.networkworld.com/article/2232181/cisco-subnet/understanding-dual-stack-lite.html So something like 4in6 + carrier grade NAT. I'm guessing that this may have to do with Sprint's extensive use of IPSec tunnels. I read previously that you can't do dual stack over an IPSec tunnel, it's either IPv4 or IPv6. You can get around this by encapsulating the traffic in a different protocol like GRE, but it adds more overhead. So transitioning their backend network to IPv6 only makes sense (only have to worry about IPv4 at the entry/exit points for the network). For devices like my Airave, which are connected via IPv4 (Verizon Fios is still IPv4 only...), that means that the phone is assigned an address in the 192.0.0.1-192.0.0.7 range, which is then encapsulated in IPv6, which is then encapsulated back to IPv4, encrypted and encapsulated into UDP, and sent over the VPN. No wonder the MTU on Airaves and Magic Boxes are so low, so many encapsulations... So I wonder if this also means that devices that are assigned routable IPv4 addresses (r.ispsn) also have this v4 -> v6 encapsulation for transit over Sprint's network?

Yes that's true. And the modem only has a memory for a certain number of sites. If you're always traveling to new areas and not home that often, it will eventually learn your home network, but then when you leave for a week to a new area and travel around, it gets overwritten with new data and has to learn it again when you get back. The local network won't learn that the magic box is there necessarily (meaning it won't actively move you to it, or suggest you move to it). But every time a cell event happens (changing bands, changing carriers), and sometimes just randomly, the network sends a "system information block" message. This contains a lot of things, but one of them is a list of earfcns that the phone should look on for a signal. The magic box and small cell earfcns are always in this list. The others are the active earfcns in the area. Sent from my Pixel 2 XL using Tapatalk

Samsung equipment was recertified for 15x15 in January apparently. I'm pretty sure it's live in some Samsung markets. Pittsburgh got the second 5x5 carrier a couple months ago, so after the recertification. Sent from my Pixel 2 XL using Tapatalk

Oh I know they shouldn't. But they currently are (Pittsburgh is 5x5 + 10x10 contig instead of a 15x15). Or in a situation where Sprint has more than 20x20 contig (if that exists), since that's the maximum LTE carrier width. Sent from my Pixel 2 XL using Tapatalk

They can use the second carrier that is on the macros. Eventually Sprint will refarm more PCS for LTE. In a lot of markets they're down to only 5x5 of CDMA, so no advantage to shut down more until they're ready to cram CDMA into the LTE internal guard bands (or add a 3x3 B25 carrier). They should be able to fit a single CDMA carrier between each 2 contiguous B25 carriers. They're already doing this with the Airave 1x carrier (T-Mobile does it as well with GSM). I suspect we'll see that at the evdo shutdown, and it will probably remain on existing sites until the equipment is replaced. Sent from my Pixel 2 XL using Tapatalk

Not if the macro is still using that spectrum for CDMA. It would interfere. Sent from my Pixel 2 XL using Tapatalk

I mean they CAN... Add B41 radios at the ODAS head end and swap the antennas for B41 capable ones. Plus some other things. Not sure if the existing wiring can be used as is, but I'm going to guess it probably can be. Sent from my Pixel 2 XL using Tapatalk

Oh yeah they can. Hmm, not sure how I missed that. And yes, that is the current band layout. That's Alameda county in California (SF area). As of 2 weeks ago, the second b25 carrier is still at earfcn 8115, so a center downlink frequency of 1937.5 MHz. Sent from my Pixel 2 XL using Tapatalk

Ahh. So they're just b25? The antenna at the top looks like the usual B41 small cell antenna, just slightly shorter (though it was distortion in the pics), so I had assumed that's what it was. Sent from my Pixel 2 XL using Tapatalk

Hmm, I don't see the usual relay antenna, nor do I see an enclosure that they hide them in in some cities. Do you know if that cabinet next to it associated with the small cell? I ask because if there's no relay, then these might be one of the more rare non-relay small cells. Do you see one or two carriers coming from it? Or is it not live yet? Sent from my Pixel 2 XL using Tapatalk

It is, it just further up the page. It doesn't all fit on one screen, I was just showing relevant information Sent from my Pixel 2 XL using Tapatalk

Nope. All the other carriers are already aligned. Sent from my Pixel 2 XL using Tapatalk

Some markets, such as most of Northern California (SF, Sacramento, etc) only have 30 (15 fdd) MHz total, and it's not contiguous. Sent from my Pixel 2 XL using Tapatalk

I was wondering the same thing. I'm not sure how LTE roaming is actually done, if it's part of the PRL or not (I suspect not). I suspect that it's possible though, perhaps as a config pushed to the modem. What was seen in DC is that T-Mobile may be broadcasting the Clearwire PLMN for Sprint roaming. This still shows as roaming on the device, wheras the Clearwire PLMN from Sprint equipment does not. Several markets (DC and NYC for example) still have Clear equipment, and thus the Clear PLMN, in use. I suspect that the device will happily connect to the Clear PLMN when the signal gets low (likely via a manual scan only due to low signal, since it won't be broadcast as neighbors. ie, the network will not preemptively move a device there and the device won't know about it with a normal signal level). And only after connecting will it discover it's roaming and be configured as such. However I'm not sure if it actually works that way, so hopefully someone with more knowledge of the technical aspects can chime in. Sent from my Pixel 2 XL using Tapatalk

Report it on the bug tracker? I've read there might be magisk hide issues so I'm holding off on the upgrade for now Sent from my Pixel 2 XL using Tapatalk