Mumble/iCW on Linux

Just a quick post so I don’t lose this command… (!)

$ parec --latency-msec=10 -d alsa_input.pci-0000_00_1b.0.analog-stereo --stream-name=Sidetone-source | pacat --latency-msec=10 -d alsa_output.pci-0000_00_1b.0.analog-stereo --stream-name=Headset-sidetone &

I’m setting up for iCW (Internet CW) on Linux and this is the pulseaudio pipe command to get a low latency monitor of my laptop’s line in (FT-817 audio is plugged in as a keyer) to my headphones.  By default, if I load the pulseaudio loopback module, the latency is far too high to work the keyer… but all those months trying to get pulse working for the network radio setup have paid off!  Instead of using pulse’s loopback module, the command above pipes the specified input source to the specified output sink and allows me to specify a target latency.  10ms is just a first guess here but it seems to be OK.

More to follow, probably a new page when I’ve got it all working…

Notes on Linux on a Dell Inspiron 17 5000 (2014, model no. 5748)

Driven by changes in daily use and a need for a bigger screen, I have decided to retire my venerable Toshiba Tecra M9 laptop from active duty and replace with a 17″ laptop.  But 17″ laptops have fallen out of favour with the computer manufacturers over the last few years and the whole laptop market seems to have taken massive steps backwards choosing style over functionality in many important areas.  Well, this is the world we live in and after looking over the main manufacturers models I’ve chosen a Dell Inspiron 17 5000 (model 5748) mainly because it was the cheapest I could find with a full HD (1920 x 1080) 17″ screen and Dell have a good history for Linux compatibility.  The model is new enough that there is little information on its Linux compatibility so I write this post in case it helps others.

Running Linux live from USB:

The laptop arrives with Windows 8.1 installed and so uses the new (well, new to me!) EFI secure boot system.  Ubuntu 14.04 and Fedora 20 live USB sticks were able to boot while this was enabled.  This needs to be disabled in the BIOS to boot Linux Mint 17 (power on, hit F12, switch the BIOS boot option to Legacy – Secure Boot Off, boot from USB…).

Ubuntu 14.04 64-bit boots and almost everything appears to work on the Live version, only the wireless network is missing.

Fedora 20 64-bit boots and most things appear to work but no touchpad and no wireless networking.

Linux Mint 17 64-bit Cinnamon and MATE versions boot and almost everything appears to work on the Live version, only the wireless network is missing.  I have installed Linux Mint 17 64-bit Cinnamon version on a new 128GB Solid State Drive, removing the Dell hard drive with Windows 8.1, this is left on the shelf for a rainy day…

Function keys:

Strangely, in the BIOS the multimedia/function keys are set to be multimedia keys by default and you have to hold the ‘Fn’ key for them to behave in the normal function key way.  Because it’s set in the BIOS this applies to both Windows and Linux.  At first I thought the laptop functions keys (brightness, volume control, etc.) weren’t working in Linux but actually they do once you’ve figured out if you have to press the ‘Fn’ key or not.  Is this normal these days?

Wireless networking:

The standard wireless network card the laptop ships with isn’t supported by the wireless drivers in any of the Linux distros I tried.  No problem, for £17 I simply upgraded the internal wifi card to an Intel 7260 wireless card which is well supported in Linux and adds 5GHz capability.  It is also the same card used in the next model up, the Dell Inspiron 17 7000 so I expected it to be compatible if Dell had done any white-listing in the hardware.  The card takes just a couple of minutes to install and works as soon as you boot into Linux Mint 17…


So far I’ve been unable to identify the manufacturer of the touchpad used on this laptop.  It works as a basic touchpad but I have no multi-touch functionality in Linux Mint.  Knowing the manufacturer is probably the first step in ensuring the correct driver is running in Linux.  It’s doesn’t seem to be a Synaptics touchpad, xinput list output as follows if it helps anyone…


I could write more on the modern design aspects of this laptop (keyboard, touchpad, glossy touch-screen…) but I think I’ll leave it there as I start to sound like an old man.  Once you sort out wireless networking, this laptop runs Linux very fast, don’t get caught out by the function keys and the secure boot thing.

G7UHN is now invisible!

G7UHN has entered a new phase this weekend – the home station equipment has disappeared from sight and is now located on a shelf in a utility cupboard!  Operation of the station is enabled by a pair of Raspberry Pis serving out audio, serial and video feeds to a laptop computer which can be located anywhere in the coverage of the home wireless network.  The arrangement of hardware needs a bit of tidying up but this ‘remote’ configuration is now fully functional and I have been making my first digital contacts this weekend with good reports from around Europe:

G7UHN on a shelf

The setup is described in some detail on this page (I’m just catching up with my notes now).  Here’s a screenshot of my new ‘shack’ in operation:

Operating data modes from the laptop...
Operating data modes from the laptop…

This project has taken some time to get up and running but in doing so I’ve learned a lot and my Linux skills are now probably creeping out of the ‘beginner’ zone!

Note (November 2017): This is a bit of an old post (but it shows how long I’ve been running the radio in a cupboard!).  I presented an updated configuration at the 2017 RSGB Convention, slides and stuff from the “Low Cost Remote Radio” talk are on this page.

Remote audio improved…

A quick post.  I’ve just discovered an improvement to the remote audio software I’ve been using to stream audio from my SDRs in the loft to my laptop over the home network.  Previously I have been using IPSound and, while excellent for connections between Windows PCs, it has some trouble running under Wine in Linux which is my normal mode of operation.  In the past year or so there has been a great deal of material popping up on the Internet about remote operation of amateur radio equipment and I’ve now come across DF3CB’s excellent RemAud which really follows on from the groundwork laid by IPSound.  I’ve just installed it using Wine in Linux Mint 15 and it works a treat!

Linux Mint – A Linux I can work with?

It seems like I’ve spent every evening for the past three weeks tinkering with my laptop, a Toshiba Tecra M9. I’ve been trying different Operating Systems since a scratch on a Windows 7 disc forced me to look for an alternative. I tried going back to the factory Windows Vista Business image and then upgrading to Windows 8. This looked OK for a short while but I guess the new Windows regards the Tecra as too much “legacy” tech as I’ve had innumerable problems with freezes, reboots and general crashing. Given up on that.

Over to Linux then, here is another point in my life when I’m going to give Linux a go as a general day-to-day OS. The point of this post is that it may be useful to anyone trying Linux on a Toshiba Tecra M9 and finding problems when they close the lid. Suspend functionality in Linux seems shakey at best. There are many reports of laptops freezing when the lid is closed, various threads point towards setting “Do Nothing” as the action on lid closing, disabling screensavers, etc. but I’ve had no joy in Ubuntu 12, Fedora 17 or Kubuntu 12. Linux Mint 14 however does appear to work. I’ve still had to set the Power Management action on lid closing to “Do Nothing” but the laptop now returns to where I left it when the lid is opened. Huzzah!