RimuSDR for Linux — Now Available

NV0E

RimuSDR v1.1.13 — Release Announcement

RimuSDR Suite v1.1.13 is now live. This is our largest release so far: 15 enhancements and 68 fixes across RimuSDR, RimuDAX, RimuCAT and the shared API layer. The theme is performance and stability - a much faster panadapter, lower CPU use throughout the audio path, and a broad sweep through crashes, slice handling and CAT behavior.

RimuSDR Suite can be found here: rimusystems.com

Faster and Lighter

• Panadapter rendering - Spectrum drawing is now over 5x faster. The display stays smooth and tuning stays responsive, especially while dragging slices.
• Receive audio - Reduced audio processing overhead that could cause glitches under load, most noticeably on Raspberry Pi.
• RimuDAX - Lower CPU use across the audio path and the on-screen meters. Under overload, the oldest buffered audio is now dropped rather than the newest, so a stall no longer replays roughly 50 ms of stale audio before catching up.
• Native Wayland on Linux - Linux packages are no longer forced through XWayland and now run natively on Wayland where the desktop provides it. This also clears the control flicker on hover.
• Fewer dependencies - RimuDAX no longer requires PortAudio or JACK, and the AppImage no longer carries them.

New in This Release

• Standardized color themes - Display Settings now offers two schemes, Neutral (the existing look) and Deep Teal, plus an optional High visibility control outline. These replace the old Default/Medium/High contrast levels and apply on restart.
• Color-blind accessibility - Permanent and temporary TNFs are now distinguished by shape as well as color, and the RIT carrier and RTTY space lines follow the same color convention as the tuning line, so it is clear which slice each line belongs to.
• Network Diagnostics history graph - Latency over selectable windows up to 24 hours, with transmit periods shaded behind the trace.
• Antenna Genius on another subnet - Controllers outside the local network can now be reached with a manually configured remote connection, rather than relying on discovery.
• Power Genius XL fan control - Direct control of a connected amplifier's fan mode (STANDARD, CONTEST, BROADCAST). Off by default.
• RAC Canada and RSGB UK band plans - Canadian and UK sub-band plans now sit alongside ARRL US and the IARU regions. Our thanks to Jonathan, G4IVV, who contributed the UK data.
• RimuCAT: VFO B and split over Hamlib - A Hamlib port can now hold two slices, so VFO B and split operation work through rigctld. The VFO-mode rigctl dialect is also supported, for logging programs that require it.

Stability and Fixes

68 fixes in this release. The main areas:

• Crashes and hangs - Fixed crashes on application close and on losing the radio connection, in the USB Cables window, when changing IARU region, and when starting or stopping a RimuDAX IQ channel. The API layer's disconnect path and event delivery were reworked to remove a class of crash that could occur when a radio disconnected while data was still arriving, along with several data races that could corrupt data under load. The application no longer freezes at startup or during update checks if the update server is slow to respond.
• Slice handling - Slices no longer disappear from the display after closing and reopening panadapters, muting one slice no longer silences the others, and tuning flags no longer overlap, hang off the edge of the panadapter or briefly freeze the pointer on hover. Another client's slices can no longer be dragged or edited.
• Filters and modes - The CW/Voice side panel and the filter and mode presets now follow the current mode reliably, digital mode filters recenter when the reference point changes, and the missing RTTY, CW pitch and FM edge limits have been added.
• Audio input - The PC microphone level slider now works, adjusts the operating system's own input level, mutes properly at 0, and remembers the required boost per microphone.
• RimuDAX - DAX channels no longer stop receiving audio after a multiFLEX station switch, the latency setting now takes effect, stalled audio devices are detected and reported instead of hanging, and leftover devices from a previous run are cleared at startup.
• RimuCAT - Corrections to OTRSP, Winkeyer WK1 behavior, automatic frequency reporting and passthrough cable state, plus fixes to UDP port replies and recovery, virtual serial ports and USB cable bindings.
• multiFLEX - Transmit meters no longer show another client's forward power and SWR readings, and applications are now told when another client leaves the radio.

The complete list is in the v1.1.13 release notes here: Release Notes

g4ivv

Hi Simon,

When you said "faster and lighter" I thought it best to get my Raspberry Pi out and test the new version and compare it to my normal Linux desktop 😀

OK my Pi is a Pi500+ with 16G RAM (bought before the RAM price madness) so good spec for a Pi. Your latest version runs beautifully on this Pi with CPU and GPU to spare:

4 panadapters all updating smoothly with resources to spare. The silent, passively cooled, Pi is just warm to the touch. Very well done!

73 Jonathan
G4IVV

NV0E

Hi Jonathan,

This is fantastic to see. Four smooth panadapters with thermal and GPU headroom on a passively cooled board is exactly the kind of outcome I was aiming for with the latest round of performance work.

What really stands out is the comfortable operating margin. That’s a huge validation for the optimizations around rendering, buffer scheduling, and the new lightweight signal path.

And I have to say, seeing a Pi500+ behave like a proper desktop-class client is deeply satisfying. It’s a great reminder of how capable these boards are when the software isn’t fighting them.

Thanks again for taking the time to test it and share the results. Really appreciate the report.

NV0E

Hi Everyone,

We’ve added a new form on our website for submitting bug reports and enhancement requests. You’ll find the link on the Support page: https://rimusystems.com/support

Up to now we’ve relied on email, but the form helps us gather all the details we need and reduces the chances of missing important information. It asks for your call sign and RimuSDR license key mainly to prevent spam and automated submissions.

If you have a general question or aren’t yet a customer, please continue to email support@rimusystems.com.

NV0E

RimuSDR Suite v1.1.14 Release Announcement

RimuSDR Suite v1.1.14 is now live, with 25 enhancements and 51 fixes across RimuSDR, RimuDAX and RimuCAT. Received audio latency drops from about 450 ms to about 80 ms, MIDI controllers get a redesigned setup dialog, new actions and important transmit safety fixes, and all three applications now share one Connect to Radio dialog.

RimuSDR Suite can be found here: rimusystems.com

Lower Audio Latency

• Receive audio latency - Received audio latency is cut from about 450 ms to about 80 ms. The latency is now reported live, along with the longest gap between received audio packets, which is the number that explains a dropout.
• Uncompressed PC audio - A new RX stream setting in Radio Setup > Audio > Output Device asks the radio for the uncompressed 24 kHz stream instead of Opus, for operators on a wired LAN who can hear the codec on CW. It applies the next time PC audio starts, so the Radio/PC toggle gives a two-click comparison. SmartLink connections always use Opus.
• Deeper RX buffering - The RX buffer now reaches 2000 ms, with a spin box beside the slider for exact values, so it can ride out a link stall longer than about 300 ms. The default is unchanged at 60 ms.

MIDI Controllers

• Redesigned MIDI Controller dialog - The dialog and its binding model are now complete, and the first-time setup guide was rewritten with it. A binding can also be entered by hand, choosing Note or CC and its number, which helps when a device sends several events per gesture.
• New MIDI actions - A [TX] PTT action keys the radio on Note On and unkeys it on Note Off, in modes other than CW. A held Tune action drops the carrier when the control is released. Also new: seven RX actions for the CTR2-Max, a PC volume action, a CW sidetone level action and a panadapter zoom action, and the ATU toggle action now works.
• CTR2 templates - The CTR2-Dial and CTR2-Max templates were updated with new action mappings, including knob-to-button actions.

New in This Release

• One Connect to Radio dialog - RimuSDR, RimuDAX and RimuCAT now share one dialog for local network, direct IP and SmartLink connections. In RimuSDR it opens by itself at startup and after a disconnect. In RimuDAX and RimuCAT it opens from the menu only, and the separate "Connect via SmartLink..." menu entry is gone.
• Connection Statistics dialog - The Statistics and Network Diagnostics dialogs are now one dialog, opened from Settings > Connection Statistics... or the network icon in the status bar, and View > Statistics... is removed. It gives two separate verdicts, Network (is the link delivering packets?) and This Computer (is this PC keeping up with what arrived?), and a new table on the Errors tab shows real network loss per stream. The network graph also gained a jitter trace beside latency.
• Panadapter - Zoom is now continuous, with a slider between the +/- buttons that runs between the radio's own bandwidth limits, and one +/- press is still exactly one octave. Slice tuning flags can be minimized by clicking the slice letter, with a "Start Slices minimized" preference, and the Pan Display panel gained the Weighted Average toggle and the Floor row.
• Model-aware power metering - The RF power meter scales to the rated PA power, for example 500 W on the AU-520, and the SWR meter's red zone follows the PA type. Aurora PA efficiency and temperature meters were added.
• Filter preset store - Display Settings can now choose which filter-width preset store is used: automatic (the radio's when its filter-preset feature is licensed, otherwise this PC's), or either one forced. The choice applies without a restart, and the screen says which store is live and why.
• Slice DSP levels - Every leveled slice DSP function (NB, NR, ANF and the rest) can be adjusted from the DSP page through one slider with a dropdown selector, and a CW APF level slider was added.
• Control usability - The AGC-T, squelch, AF gain and pan sliders show their value in the tooltip, the mouse wheel steps the RIT and XIT boxes in 10 Hz steps while they have focus, and RF gain in the panadapter ANT dialog is now a slider.
• System Info and logging - System Info now reports the connected radio and its accessories (ATU, GPS/GNSS, amplifier). A radio's refusal of CW keying or a CWX message now leaves a usable trace in the log.

Stability and Fixes

51 fixes in this release. The main areas:

• Transmit safety with MIDI - A held MIDI Tune, PTT, key or paddle no longer stays keyed when the controller is unplugged, and it is released whenever the transmit slice changes, so a carrier can no longer follow a slice to another band. Pressing controls while the MIDI Controller dialog is open no longer keys the radio, asserts MOX or starts a tune.
• MIDI keying and knobs - CW keying from MIDI now follows the transmit slice's mode, so a straight key no longer sends a tone in USB, and a paddle release that arrives without its press now sends its tap instead of being discarded. Knobs other than the VFO now act as absolute 0-127 sliders, matching the default output of CTR2 controllers, and a knob wired as a wheel now drives RIT, XIT and the slice DSP levels. Fixed a crash when unplugging a USB MIDI controller on Windows 11.
• ATU and Tuner Genius - Clear ATU Memories now asks for confirmation and defaults to No. It previously cleared every stored tune solution the moment it was chosen, with no warning and no undo. With a Tuner Genius XL and two slices on different transmit antennas, RimuSDR now checks the active slice rather than the transmit slice, so the ATU indicators, the radio's internal ATU and ATU memories are handled correctly, and a refused Tuner Genius tune is no longer silent.
• Audio and SmartLink - The audio stream created at connect no longer starts about 150 ms deeper than a restarted stream. Over SmartLink, the RX buffer now fills to the depth the slider asks for, where it previously never held more than about 30 ms, and an expired saved sign-in now asks for the password instead of leaving the dialog at a dead end. The connect dialog and the SmartLink Manager now share one SmartLink session, which ends when the manager closes.
• Panadapter and tuning - A zoomed-out slice can now be tuned, the Single click to tune setting can now be turned on and also works on the waterfall, and the mouse no longer sticks under a slice flag with Tune Guides on. The waterfall time scale now follows the Rate control, and the Pan Display Avg slider is no longer stuck at zero. A slice created by an external client, such as a Node-RED script, is now tracked correctly, fixing intermittent TX-focus problems.
• Filters, CW and controls - The factory filter-width presets now match the radio's own, and the RimuSDR-only SSTV, FDV and PSK presets are removed. Escape now aborts a CWX transmission from anywhere in the CWX window, and the P/CW panel no longer stays in phone mode after enabling split in CW. Two-way switches such as the Radio/PC audio selector can no longer end up with neither side selected, and the FlexControl button is no longer overwritten by auto-detection at every start, so it can be turned on before the knob is plugged in.
• Licensing and Windows - A license could be rejected after a restart on an unchanged machine, asking for the key again. Activation is now recognized reliably. On Windows, more kinds of crashes now produce a crash report, reports show function names, and the installer no longer adds about 5 MB of files the application never uses.
• RimuCAT - The Winkeyer port no longer stops responding after the radio refuses a CW send, for example with a slice in the wrong mode or another client transmitting, and a Winkeyer port with no radio bound is fixed too. Winkeyer statistics no longer count incoming data twice.

The complete list is in the v1.1.14 release notes here: Release Notes

g4ivv

Wow, thank you Simon! 

I have just had a quick play with this release and I am so pleased you were able to add the uncompressed audio option for those of us that use the Flex over a LAN connection. The receiver now sounds lovely on CW and the latency improvements are really noticeable. 

I'm using RimuSDR mainly on my Raspberry Pi 500+ and it runs beautifully on that. Zero dropped packets using the uncompressed audio and minimal audio buffering. I think you've really set the bar very high with this release, I'm really happy with it. 

RimuSDR on Linux is my daily driver and very highly recommended - for me it's better than SmartSDR (uncompressed audio) and I don't have to deal with Windows poor latency, unexpected updates etc.

Many thanks and best 73,
Jonathan G4IVV

NV0E

Hi Jonathan,

Thank you so much for the note, I really appreciate it. I’m glad the new features are working well for you, especially the uncompressed audio option over LAN. Hearing that CW now sounds the way it should is great feedback.

I'm glad the latency improvements have helped too. We can thank Mark Smith from Halibut for identifying that issue.

Thanks again for all your support.

NV0E

Hi Everyone,

Last week I introduced a new update option: an APT repository for RimuSDR, RimuDAX, and RimuCAT.

If you’re on a Debian‑based distribution (Ubuntu, Linux Mint, Debian, Raspberry Pi OS, and others), you can add the repository using the command shown on the downloads page: https://rimusystems.com/download .

Look for the section titled: 'Install with automatic updates'.

After that, updates arrive automatically through your system’s software updater or via "apt update && apt upgrade". This removes the need to manually download three separate packages for every release and makes it much easier to stay current.

The individual package downloads are still available.

NV0E

RimuSDR Suite v1.1.15 Release Announcement

RimuSDR Suite v1.1.15 is now live, with 19 enhancements and 32 fixes across RimuSDR, RimuDAX and RimuCAT. This release delivers a more reliable, polished experience, with meaningful upgrades across CAT, band plans, performance and radio connectivity.

RimuSDR Suite can be found here: rimusystems.com

New in This Release

• RimuCAT for Windows - RimuCAT is now also available for Windows, with its own installer. As on Linux, it supports TCP, UDP and hardware serial ports. On Windows it does not support virtual serial ports. In addition to the regular port types, RimuCAT supports the Hamlib protocol and Wavelog integration, bringing those options to the Windows platform.
• Second row in band plans - Band plans can now have a second row of sub-band segments, so overlapping allocations are easy to see. Plans with one row look as before.
• WIA Australia band plan - The WIA Australian Band Plan is now built in. It uses the second row to show CW across a whole band while phone and data cover parts of it. Choose WIA Australia in the Band Privileges File list in Display Settings. This plan currently only includes the Advanced license class.
• Slice Options - Display Settings has a new Slice Options tab with the slice behavior options from SmartSDR for Mac, all off by default. The TX slice can become the active slice when you transmit, or the active slice can become the TX slice when you select it. Slices can keep their place on screen and move in frequency when you drag the panadapter, and the panadapter can stay centered on the active slice. Slice Synchronization keeps two slices at a fixed offset in Hz, so tuning either one moves the other.
• Spot color overrides - Spots Settings has a new Colors group, to draw every spot's text in one color and set its background color and opacity. This helps colorblind operators when spot colors are hard to tell apart. It is off by default.
• Undocked panel positions - Undocked panels now reopen where they were left, including on a monitor to the left of or above the main monitor. A panel saved on a monitor that is no longer connected opens on a connected one.
• RimuCAT: Wavelog port status - A Wavelog port that cannot reach Wavelog now turns red in the Ports list, with "Not reachable" under its name, and turns green again when Wavelog answers. Before, it could stay green while every logbook update was dropped.

Connecting to Your Radio

• Last used radio - The Connect to Radio dialog now shows and selects the radio that "Reconnect at startup" will connect to, so Connect or Enter is one action. The checkbox now names the radio.
• Reconnect at startup by IP address - "Reconnect at startup" now works for a radio reached by IP address, for example over a VPN. Before, it looked only on the local network and gave up after 10 seconds.
• Saved IP addresses - In all three applications, the name you give an address on the "By IP address" page is now saved. A new "Forget this address" link removes a saved address.
• Dialog fixes - The "Free up this radio..." link now opens the Disconnect Station dialog, and the "Low bandwidth" option now shows only on the SmartLink page. Changing radios while a connection is still being made no longer crashes RimuSDR or applies the first radio's details to the second.
• RimuDAX and RimuCAT - Both can now connect to a radio that another station is using, including over SmartLink. A saved SmartLink account with no usable sign-in now opens the sign-in form instead of stopping.
• SmartLink timeout - A SmartLink radio that does not answer, for example with a VPN down or the radio turned off, now fails after 15 seconds instead of about two minutes.

Lower CPU and Network Use

• Panadapter and waterfall - RimuSDR now uses less CPU while the panadapter and waterfall are running. It no longer repaints parts of the window that haven't changed, and it draws the panadapter more efficiently. On a test PC connected to a FLEX-6400 with one slice open, RimuSDR went from 53.7% to 44.1% of one CPU core.
• FlexControl on Linux - Checking for the FlexControl knob used about 2.4% of a CPU core while the knob was unplugged. It now takes about one forty-sixth of the time.
• RimuDAX: DAX TX - DAX TX audio is now sent to the radio in its reduced-bandwidth mono format, about 3.7 times less data on the network, as SmartSDR does.

Stability and Fixes

32 fixes in this release, including the connection fixes above. The other main areas:

• RimuCAT transmit state - For about 12 ms after a program unkeyed through RimuCAT, a TX status query could still answer "transmitting", and an OTRSP transmit-slice switch could go ahead while the radio was still transmitting. Replies now read receive from the unkey onward, and the OTRSP switch waits until the radio has stopped transmitting.
• RimuCAT - Filter presets chosen with ZZFI or ZZFJ in CW and digital modes are now placed on the signal, so a digital mode no longer stops decoding. Two ports on the same slice, such as WSJT-X and a logger, now both follow the S-meter, and Winkeyer ports on the same radio both get character echo. Radio loss is now detected after a manual reconnect, and a port type can no longer be cleared in the Add/Edit Port dialog.
• RimuDAX audio - A program such as WSJT-X reading a DAX channel now resumes by itself after RimuDAX restarts, instead of receiving corrupted audio. A channel turned off and on recovers its audio, the Mic channel returns immediately, and a channel's label shows its real state.
• USB bit cables - In the Bit Configuration table, the headings sat one column to the left of their boxes, so a frequency range entered by following them was saved wrongly and the bit never switched. The headings now line up, and frequencies such as 14.07025 MHz are sent to the radio exactly.
• License deactivation - Help > Deactivate License now removes the local license when the server says this computer holds no license slot, instead of reporting that the server could not be reached. Other refusals now show the server's message.
• Import/Export Profiles - The dialog now shows export progress, shows import categories only after a file is loaded, and clears them after a successful import.
• Linux packages on older systems - The .deb packages now require glibc 2.38 or later. On Ubuntu 22.04, Debian 12 and Raspberry Pi OS Bookworm, apt now refuses the install instead of installing an application that fails at launch.

The complete list is in the v1.1.15 release notes here: Release Notes