Raspberry Pi - session n

First of all, when did you last see an organ grinder?

Today's Q and A session revealed a few things. Dave made copious notes before setting off early for the theatre. But for those who couldn't make it I made a few as well...

Software Mentions

I mentioned it and then couldn't get to the examples on the internet. The club house is a victim of a 'slow internet' connection.

GNU Plot home page  
Gnuplot Primer 
Plotting sensor data using GnuPlot 
interfacing early 90’s HQ digital oscilloscope from LINUX 
FIR Filters by Windowing - using gnuplot 

GIMP - Graphics Manipulation Package 
4 Themes That Will Make GIMP 2.8 Look and Work Like Photoshop 

LinPsk - PSK31 for Linux  [download from Sourceforge]
A Slice of Raspberry Pi

WSPR on the Pi.
/WsprryPi forked from threeme3/WsprryPi
Raspberry Pi QRP TX Shield for WSPR on 20 Meters 

Also mentioned

A Cross Platform and Open Source Electronics Design Automation Suite
Thanks Nic!

Audacity - Audacity® is free, open source, cross-platform software for recording and editing sounds.

Audacity does work on my 'old' Pi. But would work much better on a later model. JB


'Issues' in ugrading Lubuntu

When I made my main PC a dual boot Windwoes XP and Lubuntu, little did I realise that my hard disk was going to run out of inodes...

On researching this 'issue' [we don't call them problems any more], I found that lubuntu or ubuntu keeps updating the kernel. Whilst not removing the old ones. Auto remove [in apt-get] does not flush the old ones. So gradually I had used up all my inodes. This became apparent when I tried to install some new software. It also ran out of disk space.

So when I had a message telling me I had an 'issue' with an update/upgrade with disk space, I checked using 'df'. Nope someone wasn't telling the whole truth. Df said I had a few Gigabytes to play with. So what was wrong?

[Use df -i to show inodes]
More research said that I should remove the old kernels, thus freeing up the inodes. Well I did and we went back to the happy situation. For a while. Maybe two months...

Some months ago I had removed [with extreme prejudice] Windwoes XP. I no longer touched/rebooted into XP. I did not need the XP taking up space on my boot drive. So I made it an ext4 drive and used it for downloading storage. In previous years as drives got bigger and bigger, it was necessary to re-install Windwoes to a newer larger drive. This could take days of transferring settings ensuring all the little things like country got set correctly. In one case I forgot to set the country to South Africa, all the Office settings of course used US spelling! This needed a re-install.

Now for the good part. I backed up my home directory [folder in Windwoes] and my spare part [downloads]. Commence install of lubuntu 15.10...on a whole disk not a partitioned one of 30GB each.

A couple of hours later, I restored my backups to the wide open space on the same disk. When I run df -i now I get loads of inodes. No 'issues' and hair pulling.

I should tell you that the disk drive is a Samsung solid state 60GB disk. Which has performed for several years superbly. It really sped up Windwoes, booting in 4 to 5 seconds. Unfortunately the speed was beaten by an identical PC running Ubuntu!

Now I am happy to boot into lubuntu in a matter of about 3 seconds. But I cannot take a sip of coffee between switching on and logging in!