I made a ukulele tuner web app

close up of a ukulele
Ukulele by texasfeel  (CC BY-ND 2.0)

I got sick of all the ukulele tuner apps so I decided to make my own. The best ukulele tuner app I’ve found on the iPhone works by repeatedly playing the note you are tuning to rather than trying to analyse the audio and display the frequency of the note it detects. The human ear is still better than software at doing that in my opinion.

It’s pure html and javascript. I used the howlerjs javascript framework for playing the audio as I found the basic javascript audio functions not precise enough for the looping.

The audio samples came from freesound.org courtesy stomachache.

Ukulele Tuner

Origami platonic solids

I’ve been making some of these platonic solids in origami. Thanks to John Montroll’s books


From left to right. A tetrahedron, a cube and an octahedron.

Poor man’s router with wedge fail

chisel held into a block of wood with a wedge

I tried making a Paul Seller’s style Poor Man’s Router plane. It worked quite well but I couldn’t get the chisel’s blade edge to be really perpendicular to the surface of the wood. As an alternative I thought I’d try cutting a slot into the piece of timber and making a wedge to fit it to hold the chisel in place.

 

As much as I tried I couldn’t get the wedge to hold the chisel firmly enough that it wouldn’t slide up once I started cutting into wood with it. I think this was partly to do with it being a bevel edge chisel. This meant there was less surface area in contact with the wood, so less friction and easier to slip.

I might try making a hardwood wedge for it. I also need to try a firmer chisel instead of a bevel edge one. The extra surface area might be enough to hold it.

Workbench progress

pine board with pine leg held in with wedge
Test fitting the wedge that secures the leg to the skirt
pine leg held into pine skirt with wedge and retainer holding wede in place
Wedge retainer fitted
two sets of pine legs held up with a pine skirt between them
At last the bench self supports with the fitting of the first skirt
thick pine workbench tops resting on the pine leg struts
Workbench tops resting on the leg struts

 

Clock Part 2

Previously…

A bit more progress on my clock. I installed the dirty pink gel filter to increase the contrast ratio of the 7 segment displays, and started cutting the final case out of red 101 acrylic. Lots of laminations.

a digital clock showing the time of 11:22
Clock
side of digital clock showing laminations of the case and the inner electronics and wires
Side of clock

 

Backup your Beaglebone Black

image of a beaglebone black with a backup icon over the top of it

Using a method I previously wrote about, it’s quite easy to backup your Beaglebone Black over the network.

ssh root@bbb 'tar cf - / 2>/dev/null' | pv -cN tar \
   | bzip2 | pv -cN bzip2 > bbb-backup-tar.bz2

It runs the bzip compression locally because presumably it will be faster than on the Beaglebone Black. I didn’t actually test that hypothesis though.

pv gives nice little indicators:

    bzip2: 1.81MB 0:00:12 [ 995kB/s] [      <=>                               ]
      tar: 36.2MB 0:00:12 [3.84MB/s] [                             <=>        ]