HydrSDR RFOne (akin to an Airspy R2)

[dave3825]

also has some version of DSD built in

I briefly looked at the link. Does it mention Dsd in there?

 

[KC1UA]

I'm not sure that the link does, but the software definitely does. I actually discovered this from a Tech Minds YouTube video.

 

[BM82557]

Does the SDR++ Brown fork support HydraSDR?

 

[BM82557]

TechMinds: A Review of the HydraSDR RFOne

Over on the Tech Minds YouTube channel, Matt has uploaded a review video of the HydraSDR RFOne. The HydraSDR RFOne is a new software-defined radio, made in the USA. The design is heavily based on the Airspy R2, and the creator of HydraSDR worked on the Airspy product design in the past. In a...

www.rtl-sdr.com

 

[dlwtrunked]

On the HydraSDR site, it says that Windows 7 is not supported, so that might be part of your problem.

I know--but one person said he has it running in Win 7.

 

[EricCottrell]

As I said it did run under Windows 7, but had a rendering problem with the top toolbar icons when the side menu was open. It went back to normal when the side menu was closed. I was able to receive signals.

There is a new HydraSDR firmware version, v1.0.2, which I upgraded my unit from version 1.0.0-rc2. One change is the HydraSDR now has an USB.org registered VID 14511 / 0x38af with PID 1 / 0x0001. This does not affect the current version of the host tools or SDR++ since it recognizes the old OpenMoko VID/PID and the new VID/PID.

However this breaks using Airspy R2 support in programs. SDRSharp, DSDPlus Fast Lane, and Unitrunker do not recognize the new VID/PID. This means that any firmware upgrade or the change to using v1.0.2 in production will break using Airspy R2 support.

73 Eric

 

[EricCottrell]

I started to use the HydraSDR with Debian 12 (Bookworm). I installed SDR++ with the Discover installer. Of course there was no listing of the HydraSDR in SDR++ until I installed hydrasdr-host-tools with Discover and did the other install steps. It works great.

I was surprised to see an airspy driver mentioned on device insertion as I have not installed libairspy0. The driver is part of the kernel USB drivers for video for linux two (v4l2).

[   27.945634] usb 1-2: new high-speed USB device number 5 using xhci_hcd
[   28.094627] usb 1-2: New USB device found, idVendor=1d50, idProduct=60a1, bcdDevice= 1.00
[   28.094639] usb 1-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[   28.094645] usb 1-2: Product: HYDRASDR
[   28.094649] usb 1-2: Manufacturer: www.hydrasdr.com
[   28.094653] usb 1-2: SerialNumber: HYDRASDR SN:<redacted>
[   28.117679] airspy 1-2:1.0: Board ID: 00
[   28.117683] airspy 1-2:1.0: Firmware version: HydraSDR RFOne v1.0.0-rc2 2024-09-15
[   28.118410] airspy 1-2:1.0: Registered as swradio0
[   28.118413] airspy 1-2:1.0: SDR API is still slightly experimental and functionality changes may follow
[   28.118438] usbcore: registered new interface driver airspy

After I upgraded the HydraSDR firmware, this is what Linux shows on device insertion. The kernel airspy driver is not loaded.

[ 1251.691201] usb 1-2: new high-speed USB device number 7 using xhci_hcd
[ 1251.840102] usb 1-2: New USB device found, idVendor=38af, idProduct=0001, bcdDevice= 1.00
[ 1251.840115] usb 1-2: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 1251.840121] usb 1-2: Product: HydraSDR RFOne
[ 1251.840125] usb 1-2: Manufacturer: www.hydrasdr.com
[ 1251.840129] usb 1-2: SerialNumber: HYDRASDR SN:<redacted>

I found out the reason the serial number list does not work with DSDPlus Fast Lane. The SerialNumber descriptor is a different length between the Airspy and HydraSDR.

I looked at the firmware repository for the HydraSDR firmware. I noticed a comment that HydraSDR is based on the HackRF project. This is the same as Airspy.

The changes from v1.0.0-rc2 (2024-09-15) to v1.0.2 (2025-07-18):
Hardware Board ID goes from 0 to 1 (HydraSDR RFOne Official Board usb.org VID 14511/0x38af VERNOUX BENJAMIN / PID 0x0001)
USB VENDOR ID goes from 0x1D50 to 0x38AF (usb.org VID VERNOUX BENJAMIN)
USB PRODUCT ID goes from 0x60A1 to 0x0001 (PID HydraSDR RFOne)
USB Descriptor Type string goes from "HYDRASDR" to "HydraSDR RFOne"

So there are no functional changes, just establishing the proper descriptor information for the product.

73 Eric

 

[boatbod]

I was looking at gr-osmosdr and it seems the HydraSDR support may not have made it into the Osmocom repo, so for now you probably have to build your own from sources. It's not hard to do, but something to be aware of, nevertheless.

 

[EricCottrell]

I was looking at gr-osmosdr and it seems the HydraSDR support may not have made it into the Osmocom repo, so for now you probably have to build your own from sources. It's not hard to do, but something to be aware of, nevertheless.

The code is in the HydraSDR and PentHertz repositories, but there is no release. As mentioned, you need to build one of these.

GitHub - hydrasdr/gr-osmosdr: gr-osmosdr - generic gnuradio SDR I/O block / Mirrored from https://gitea.osmocom.org/sdr/gr-osmosdr

gr-osmosdr - generic gnuradio SDR I/O block / Mirrored from https://gitea.osmocom.org/sdr/gr-osmosdr - hydrasdr/gr-osmosdr

github.com

GitHub - PentHertz/gr-osmosdr: Mirrored from https://gitea.osmocom.org/sdr/gr-osmosdr

Mirrored from https://gitea.osmocom.org/sdr/gr-osmosdr - PentHertz/gr-osmosdr

github.com

On my list is building OP25 and seeing if it works with the HydraSDR.

I ordered another HydraSDR so I can have a pair for Trunk Tracking.

I noticed two new commands (USB vendor requests) in the HydraSDR host code. There is now a Reset command (0) that replaces an illegal command in the Airspy Driver. There is also an added Set RF Port command (28) that controls the two added RF In ports of the Rafael R828D tuner. It will be interesting to see what additional hardware will become available in Future.

73 Eric

 

[EricCottrell]

I was able to compile gr-osmosdr from the hydrasdr, but there seems to be an undocumented step. You need to run the shell script in the thirdparty directory to copy the hydrasdr include files and setup pkgconfig.

However, on my Debian 12 laptop the pkgconfig directory is under /usr/lib and not /usr/local/lib. There is mixture of /usr and /usr/local paths. I had to edit the /usr/local paths to /usr in the script. After editing, I ran the script and then was able to build gr-osmosdr with hydrasdr support.

73 Eric

 

[boatbod]

I was able to compile gr-osmosdr from the hydrasdr, but there seems to be an undocumented step. You need to run the shell script in the thirdparty directory to copy the hydrasdr include files and setup pkgconfig.

However, on my Debian 12 laptop the pkgconfig directory is under /usr/lib and not /usr/local/lib. There is mixture of /usr and /usr/local paths. I had to edit the /usr/local paths to /usr in the script. After editing, I ran the script and then was able to build gr-osmosdr with hydrasdr support.

73 Eric

I built the hydrasdr version of gr-osmosdr, installed it and everything is still good with my airspys and rtl devices. As soon as my rfone arrives I should be good to go.

Note that with 8Mhz+ of bandwidth, you really shouldn't need a second dongle to be able to trunk track

 

[EricCottrell]

I built the hydrasdr version of gr-osmosdr, installed it and everything is still good with my airspys and rtl devices. As soon as my rfone arrives I should be good to go.

Note that with 8Mhz+ of bandwidth, you really shouldn't need a second dongle to be able to trunk track

There are UHF trunk systems in my area that have channels in two or more ranges (450-455 MHz, 460-465 MHz, 470-473 MHz, 482-485 MHz).

There is a new Preview version of Unitrunker that supports HydraSDR. It would be great to have DSDPlus Fast Lane support it as well.

 

[KC1UA]

Minor addition to the above; I really like the SDR++ Brown fork for conventional searching and monitoring, given the built in DSD and ability to pipe a second audio source out (which I do for use with KGTone for CTCSSS/DCS decoding). I requested adding support for the HydraSDR at that software's Github page.

 

[EricCottrell]

This is annoying!

I ordered a second HydraSDR on Sunday and the order status has been stuck on Received for three days now. Totally different than the week before where it was quickly shipped. Digikey shows over 1200 in stock. I sent a email and the reply is the order is "currently on hold with our internal team for further review."

 

[maus92]

I just unboxed mine as this was the first day off since it was delivered. It seems to have lower noise floor than my R2s and Minis when running SDR++. It is recognized in Unitrunker 2 as an Airspy; I haven't updated the firmware yet. UT released Preview 35 yesterday that should recognize the device as a HydraSDR. Anyone have a link to the updated firmware?

 

[BM82557]

This is annoying!

I ordered a second HydraSDR on Sunday and the order status has been stuck on Received for three days now. Totally different than the week before where it was quickly shipped. Digikey shows over 1200 in stock. I sent a email and the reply is the order is "currently on hold with our internal team for further review."

Waiting on mine also.

 

[boatbod]

I was able to compile gr-osmosdr from the hydrasdr, but there seems to be an undocumented step. You need to run the shell script in the thirdparty directory to copy the hydrasdr include files and setup pkgconfig.

However, on my Debian 12 laptop the pkgconfig directory is under /usr/lib and not /usr/local/lib. There is mixture of /usr and /usr/local paths. I had to edit the /usr/local paths to /usr in the script. After editing, I ran the script and then was able to build gr-osmosdr with hydrasdr support.

73 Eric

I'm having a curiously tough time getting my gr-osmosdr driver to work with the Hydrasdr device.

The physical device is working and has been verified using hydrasdr_rx and hydrasdr_info utilities, and was reflashed with the latest firmware using hydrasdr_spiflash tool. Running the lsusb command shows the appropriate hydra device string.

A Hydrasdr version of gr-osmosdr has been successfully built and claims to have HYDRASDR Receiver support enabled (as indicated by cmake), but no apps can actually connect to the device because gr-osmosdr is complaining that there are "No supported devices found". I have made sure that every last remnant of the packaged version of gr-osmosdr has been removed, and that my apps are using the version of gr-osmosdr which I built and installed.

As best I can tell, even though I see hydrasdr source files getting compiled during the build process, it seems the hook to that code must somehow be missing.

Does anyone have any ideas what I might be overlooking?

ETA: the Hydra code is definitely present and finding the device, but for reasons I don't yet know, it's not opening properly... oh well, time to go hack the driver and find out why!

 

[boatbod]

To follow up on my previous post:

After considerable driver hacking, I have managed to get my device up and running with op25. The problems I was encountering with the out of the box code is that the Hydrasdr additions to gr-osmosdr are incomplete and as a result "args=hydrasdr" is not a valid target as a config parameter.

I suspect the provided driver code *may* work if I change the way that op25 opens gr-osmosdr and make it ask for a list of all devices before attempting to connect to a known one, but really I shouldn't have to do that. All the other supported hardware devices are properly initialized in gr-osmosdr except for Hydrasdr.

I'm going to look at this some more tomorrow evening, but for now I am happy that it's working at all!

First screen shot is the Hydrasdr running at 10Mhz tuned to the control channel of my local P25 simulcast system.
Second screen shot is my Airspy Mini running at 6Mhz tuned to the same system.
Equivalent antennas, sat on the same desk within a few inches of each other. The Airspy needs the gains turning down a bit to improve SNR, but I'm still extremely pleased with the performance of the Hydrasdr even with such little time to tweak it.

 

[dlwtrunked]

I tried the HydraSDR with HDSDR software using the Airspy dll in Win 7. Hilarious sounding audio--like a 78 rpm record played at 45 rpm.

 

[maus92]

I decided not to upgrade the firmware until SDRTrunk supports the new VIDs. For now it works with the two main SDR software applications I use: Unitrunker 2 and SDRTrunk. I did notice that the ppm correction is very small; for the Hydra: it's +0.1 vs -1.1 for the Airspy it replaces when using with SDRTrunk.