Feel like venturing into Merlin on AC18.
So, steps:
1. Download ac18_kf_V15.03.3.7(4031)cn.bin from https://drive.google.com/file/d/1P66G2SS9qc...iew?usp=sharing by prokiller1199
2. Download Asus WRT Merlin 380.70 from https://netix.dl.sourceforge.net/project/as...0_0.zip?viasf=1
3. Flash from current firmware V15.03.3.11_multi to firmware from (1) via web GUI.
4. Flash ASUS WRT 380.70 from (2).
5. Access new ASUS GUI via 192.168.1.1 and setup unifi as usual.

Could the sifus confirm the above step before I flash the router? Ministry of Finance gonna be pissed if router doesn't work

Ok done. Unifi profile setup and running. But got icon flash on the GUI says low NVRAM?
Do I need to do anything else for that?

This post has been edited by 711726: Dec 10 2020, 01:23 AM

Just did factory reset and restore the cfg file. Thanks bro!

Yeah working fine now. The signal isn't as strong as Tenda's firmware though, but I expected that

Mind sharing the link bro?
Google failed me. Can't find sites with download links.
I saw got HGG_380.70-RC version too, so not sure which one.
But basically, after flash to HGG_380.70 Final, cannot upload old config file, and need to lock Wifi channels, right?

Flashed to HGG 380.70_Final. Signal seems weaker than Tenda firmware

Enhanced mode under 'Max speed'. Does it have big impact on speed if change to Max coverage?

when I had it flashed to HGG already 100% Tx. Same router location, same device

I supposed on HGG final equal or better signal coverage, but it doesn't seem so to me..Looks like need to find another cheapass Tenda router to act as AP..AC10U out of my list, wifi can't exceed 100Mbps

Bought AC23 as AP, working as intended. Now all of sudden, my 5G WiFi on AC18 got problem. Wireless-->Professional tab shows 5GHz radio is already turned on, but I couldn't see the AP list on my phone. 2.4GHz is fine, but now for some reason cannot even see 5G network on the same router, even though on Professional tab, radio in ON.
Wireless-->Site survey also states "5 GHz radio is disabled - cannot scan that band!"

Update. Reflash with HGG 380.70 doesn't solve it. Site survey still say radio disabled. Still I cannot see my 5GHz wifi on wifi analyzer app, but Wifi icon on GUI states 5GHz band set with channel 0. Manually overriding the channels to something else (say 149), the WiFi icon will still say channel 0.

Appreciate for any help

This post has been edited by 711726: Dec 29 2020, 02:21 AM

Yeay! Working fine now!

So I'll try to make this guide as foolproof as possible

*To flash Tenda AC18 from original Unifi firmware to Merlin 380.70_HGG-FINAL *
So, steps:
1. Download ac18_kf_V15.03.3.7(4031)cn.bin from https://drive.google.com/file/d/1P66G2SS9qc...iew?usp=sharing by prokiller1199.
2. Download Asus WRT Merlin 380.70 from https://netix.dl.sourceforge.net/project/as...0_0.zip?viasf=1
3. Download Putty from Putty.org
4. Install Putty from (3).
5. Download 380.70_HGG-FINAL from Merlin 380.70_HGG-FINAL
6. Access your Tenda GUI on browser. Flash from current firmware (V15.03.3.11_multi) to firmware from (1) via Tenda web GUI via manual file upload.
7. Extract file from step (2). Login to your Tenda GUI again. This time, flash the router using the extracted .trx file firmware.
8. Access new ASUS GUI via 192.168.1.1. No need to setup Unifi for now.
9. Flash firmware from step (5) using Asus GUI. This will take a few minutes to settle.
10. Whilst waiting for step (9) to complete, open CMD. In CMD, key in 'ping 192.168.1.1 -t'. If you managed to receive response from router, this means that your router has been upgraded to HGG firmware, and you're now ready to access the router's ASUS GUI again.
11. Browse to 192.168.1.1 (Asus GUI) and proceed to setup your Unifi. Choose Unifi profile, set WiFi passwords and select PPPoE. Key in your unifi ID 'XXXX@unifi' and password. Please set a proper username and password to access the router's ASUS GUI.
12. Reboot router.
13. Access 192.168.1.1 again, go to Administration --> System --> SSD Daemon. Enable SSH. Choose 'LAN only'. Tick YES for 'Allow SSH password login'.
14. Open Putty that you've installed in step (4).In the Host Name, key in 192.168.1.1. We are going to clear nvram. Click Open.
15. New Putty window will popup, click YES.
16. Putty will now request for your router's username. Key in the username you've assigned on the router in step 17. Press enter.
18. Putty is now requesting the password to your router's GUI. Key in the password you've assigned on the router in step 11. Press enter.
19. Putty will now display '** YES MASTER! ** - RT-AC68U 380.70-HGG-FINAL '.
20. Key in 'nvram set model=RT-AC68U'. Press enter.
21. Key in 'nvram set HW_ver=170'. Press enter.
22. Key in 'nvram commit'. Press enter.
23. Key in 'reboot'. Press enter. The router will now reboot.
24. Repeat step (10). If you receive response via 192.168.1.1, then your router has finally rebooted and ready for access again.
25. Login to your Asus GUI. Go to Tools -->Sysinfo. On the Internal Storage section, you will now find your NVRAM Usage is something like 52154 / 65536 bytes. So long the value doesn't reach 65536 bytes or over, you're now good to go

PS: Seems like my usb port got no power now. Will try to clear nvram again and see if that helps. I got a router's cooler powered by USB attached to the router. Upon reboot again (after complete step (25), it doesn't receive any power from USB port anymore. It was powered on after the 1st nvram clear though

This post has been edited by 711726: Dec 30 2020, 12:36 AM

Hmmm..did that and still no power to cooler. Cross checked with powerbank, the cooler powered on. I'll try to do nvram clear again, + odmpid followed by reboot. Will revert if that solves it. Otherwise, factory reset and try again.