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hpr3083 :: Mumbling while on lockdown

Two Edinburgh-based hosts have a chat from their respective houses

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Hosted by Dave Morriss on 2020-05-27 is flagged as Explicit and is released under a CC-BY-SA license.
COVID-19, lockdown. 4.
The show is available on the Internet Archive at:

Listen in ogg, spx, or mp3 format. Play now:

Duration: 00:50:21



Two HPR hosts based in Edinburgh got together over Mumble to have a chat during the COVID-19 lockdown.


Dave’s sound was a bit distorted in this recording. Having had recent problems using the Zoom recorder as a microphone, this time the in-built microphone was resorted to, with even worse results it turned out. See the Sound processing section below if you want to know more.


Some of the topics we discussed

  • Locations for recording. Ambient noises.
  • WiFi versus ethernet. Dave has a 5-port switch on his dining table (not 8-port).
  • ADSL routers
  • Linksys NSLU2 "SLUG"
  • SheevaPlug
  • CUPS - printing and scanning with old non-networked printers
  • Legacy computing experiences:
    • Diablo exchangeable disks
    • Line printers. Fan-fold 132 column paper
    • Punched card experiences. Card sequence numbers. Card sorters.
    • Checking disks for warped platters
    • Magnetic tapes; recovering from damage.
  • 8-track tapes
  • Museum of Communication, Fife
    • Strowger switch electromechanical stepping switch telephone exchange system

Sound processing

The recording was made in multichannel mode in anticipation of problems. The distorted channel was processed by using the Clip Fix effect in Audacity, which didn’t seem to change much except reduce the sound level. It was also necessary to find and remove sounds produced by the push to talk key presses. Removal meant replacing these sounds by silence so the two channels would not get out of step. After this the two channels were merged together and silences truncated.

Lessons learned: don’t use a built-in microphone if you can help it!


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Comment #1 posted on 2020-05-29 09:40:26 by DanNixon

Groove based tape format

Is the audio format you referred to the Tefifon (

Never seen one in person but there is a good overview of it over on Techmoan's YouTube channel:

Comment #2 posted on 2020-05-31 10:50:15 by MrX

Re Groove based tape format

Hi Dan yes you are quite correct it was indeed the Tefifon, I couldn't remember its name. It certainly is a very strange device. The one they had at the museum of communication wasn't in working condition at the time, they were in the process of trying to repair it I hope they succeeded. I must thank you for bringing this up as I really enjoyed rewatching the YouTube video link you gave which gives an excellent introduction of the device. The sound quality seemed surprisingly good. I watched the video while sitting out in the sun in my back garden. All the best MrX

Comment #3 posted on 2020-06-03 22:03:05 by Windigo

Modern Sheevaplug support

Dave, I hope you'll be excited to hear that the Sheevaplug is still very well supported by Debian. I had one up-and-running with the latest version until very recently.

Here's a resource I used to set mine up:

I have a hard time justifying keeping mine running, what with the Raspberry Pi and others being so much more full-featured and powerful, but it's definitely an interesting piece of hardware!

Comment #4 posted on 2020-06-04 09:11:51 by Dave Morriss

Re: Modern Sheevaplug support

Hi Windigo!

Thanks for the link. I'd love to get my old Sheevaplug up and running again, and this looks like the site to help me do so.

I don't actually have a use for it at the moment. It had a USB disk on it and I used to use it as a Git repo (a package called 'Gitosis' I think), and could access it when away from home. Then it was a "playground" for learning about Bind. Then the disk crashed!

Anyway, this is now on my to-do list. Thank you!


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