I bought two Samsung Galaxy A13 5G phones from Google Fi for $100 each on promo, but by default, they connected in NR NSA (non-standalone) mode, which requires an LTE anchor. Performance was okay in NR NSA except in few geographic areas where LTE bands 2, 4, and 66 had high packet loss of 50-100% because of low signal or interference.
With a little effort, Samsung Galaxy phones can be put into NR SA ("pure 5G") mode. The process is similar to the Galaxy S22 (see guide by peacey8 at end), but there are a few differences. In particular, the A13 uses a Mediatek MT6769V/CU Helio G80 chipset instead of the Qualcomm SM8450 Snapdragon 8 Gen 1 on the Galaxy S22, so the serivce menus differ.
Pros and cons
Pros
- Lower latency and packet loss (sometimes/generally).
- Latest generation of cell network technology.
Cons
- Requires compatiable carrier. (In the USA, it's only T-Mobile and their MVNOs such as Google Fi and Mint Mobile.)
- Requires somewhat modern phone.
- Requires compatible cell tower. (In my area, 5G coverage is excellent.)
- T-Mobile does not support voice yet on NR SA mode. If band locking is set to NR SA, phone calls will not work. If band locking allows LTE and NR NSA, it will automatically fall back to LTE/NR NSA.
- Allowing NR SA mode requires some initial technical set up.
- Without band locking, the phone may often favor NR NSA over NR SA, even when NR SA has better network performance.
- Band locking settings (optional) gets lost after phone reboot.
- Set up varies by chipset.
Guide
This guide assumes your phone has the XAA (unlocked) CSC profile. If not, see peacey8's guide at the end. If you have TMB profile, then NR SA mode should already work. Once you have XAA, proceed here.
- On the phone, enable developer mode: go to settings (gear) - About Phone - Software Information - tap seven times on build.
- In phone settings (Gear) - Developer Options - enable USB debugging.
- Install Samsung USB driver for Windows. (Sorry, you need a laptop or desktop.)
- Launch the SamFW FRP tool on Windows.
- Connect phone by USB cable to Windows machine.
- In SamFW, enable secret code for Verizon. (You do not need to use Verizon as a carrier.)
- SamFW should stop at "Waiting for DIAG."
- In Samsung Phone app (with the blue icon), call *#0808#. (It does not work for me in the Google Phone app with the green icon.) After hitting the last pound (and before hitting the call button), the USB settings menu should appear.
- If you have two options, then you did not enable USB debugging. Start over.
- Tap DM+ACM+ADB and tap OK. (The Galaxy S22 has way more USB debugging options, by the way.)
- SamFW should stop at "Disabling DIAG."
- Then call *#0808#, and switch back to MTP.
- Phone can be disconnected from USB, if you wish.
- In the Samsung phone, app use the dialer code *#27663368378#.
- UE SETTING AND INFO -SETTING - PROTOCOL- NR -ALLOW LIST- ALLOW LIST OFF
- Three dots (top right), back
- NR5G SA / NSA mode control - SA / NSA enable
- Reboot phone.
Once it is working, you can disable the USB debugging and developer options menu on the phone, and you can uninstall SamFW.
Troubleshooting
Unlike the Galaxy S22, the *#2263# menu will not look any different on the A13. Even when NR SA is active, this service menu looks the same. It doesn't distinguish NR NSA and NR SA, so to confirm you are on SA, some options are:
- Dial *#0011#. Pick relevant SIM. Check fourth line "Serving PLMN." If you see Nr5G, it's SA. If LTE, then it's not.
- Use app such as CellMapper, Network Cell Info Lite, or NetMonster. They will all show the network type on the main page.
If you are still on LTE or NR NSA, some options:
- Check your carrier supports NR SA. Right now, T-Mobile does, while Verizon and AT&T do not.
- Check you have a 5G SIM and a 5G plan.
- Turn off wifi. (It may use LTE only for power savings.)
- Move closer to the tower.
- Move to another tower.
- Reset the connection like this: phone settings (gear) - Connections - Mobile networks - LTE/3G/2G. Wait a moment and set back to 5G/LTE/3G/2G. On our two A13, S22, and S22+ phones, we often need to reset the connection like this, and airplane mode does not seem to help. Otherwise, it may stick to LTE when NR NSA or NR SA are available.
- Disable LTE like this: in the Samsung Phone app (green app icon), call *#2263#. Tap the relevant SIM. Tap CLEAR ALL BANDS. Tap "BLOCK SET BY AP," so the asterisk goes away. Tap NR menu to enter it. Select NR ALL. Go back to main. Apply selection. This may reset after rebooting the phone.
- Alternate way to force NR: in Google Phone app (blue app icon), call *#*#4636#*#*- Phone Information - Set preferred network Type - NR only.
I tested this two Galaxy A13 phones running Android 12 with T-Mobile via Google FI. In case you want to join Google Fi, here's a referral code to get a $20 credit when you join: 2RD2V5.
On the Galaxy S22, voice calls do not work with NR SA: incoming calls go straight to voicemail, and outgoing calls stop a moment after dialing because VoNR apprently is not enabled. It is probably the same on VoNR.
Thank you much to the NR SA for Galaxy S22 guide from peacey8 and molexs's comment about the SCR01 hotspot.
