This site might not be up to date all the time!
I do this in my free time.
The Q900 is a SDR transceiver made by Guohetec in China and is available in its 4th version (V4).
https://www.guohedz.com/Q900
Since 2023 they also have new transceiver PMR-171. I own the Q900 V4 but I will try to add as much information about all versions as I can. The PMR-171 is very similar to the Q900 V4 so most things (if not all) will apply there as well (probably also the TBR-119).
New Update 2024/04/11 on the Q900 / PMR-171 TX audio / microphone issue – DD6KW site with new test videos.
Update 2023/11/08: even the firmware versions have the same numbers. 3.4.1 for Q900 and TBR-119, 3.4.2 for the PMR-171. There must be a lot in common. PMR-171 in DMR mode not having audio output on headphone jack like the Q900 would also mean that they have a lot in common.
Update 2023/11/29: The mainboard of the PMR-171 and the Q900 (V3/V4) are the same with some small changes. see groups.io.
So most things should also apply to the PMR-171. Feedbacks in the WhatsApp group would also support that.
These are the known versions and names:
– V1: Q900 and Ailunce HS2
– V2: Radioddity QR20
– V3: Q900 and Ailunce HS2 mk 2022
– V4: Q900
If you don’t know what version you have: Long press MENU and select ABOUT. There you should see hardware and firmware versions.
Creating this website is my own idea and I will do the work in cooperation with the Q900/PMR-171 community. And hopefully I will get some help to fill this site with information.
There is a WhatsApp group for the community that was created by the official seller of the Q900 (POTOLAB Store on AliExpress). Members from Guohetec are also in the group.
This is a good place to get help from experienced users and Guohetec. It is also a good place for exchange.
Join the group if you are interested. But you won’t see what was written before you joined and it is hard to find information in a chat group. One reason for this website.
You can find the link to the group in the pdf file: group link
Update 2025/10/20
The link to the WhatsApp group has been updated!
In the meantime Guohetec had problems with their WhatsApp account and are no longer Admin of the group. But they rejoined.
They also created a new group „GUOHETEC family“. Most of the active members are in both groups.
group link
A Forum was created by one of the community members. The provider offers the forum for free, but a FAQ section would be a paid service. Another reason for this website. You don’t need to register to groups.io to read:
https://groups.io/g/Q900/topics
Update 2023/10/25
I added a quick overview of things that are good to know about the Q900:
Things to know about the Q900
Then I found another discussion about the Q900 that does not seem to be connected to the community mentioned above with a focus on use with Linux:
Ailunce HS2/Radioddity QR20/Q900 SDR Transceiver
Facebook group for the HS2:
Ailunce HS1 & HS2 SDR HF Transceiver Club
(The Ailunce HS1 is a another version of the MCHF 0.6.3)
Facebook group for the PMR-171:
Guohetec PMR-171 | Facebook
Contact:
If you have any sugestions or find something not accurate on this website, please contact me.
I’m also looking for help filling this website with content…
My email can be found there: Callsign Database – QRZ.com