To quickly find half-diminished chords we'll start with the diminished chord because it's an easy shape to remember. You can play this anywhere on the ukulele. Any ukulele will work: soprano, tenor or baritone.
In the previous post you discovered that if you take any note from the diminished chord and move it down one fret you get a dominant 7th chord. A similar thing happens if you move any of the notes up, except doing this gives you half-diminished chords. Half-diminished chords are commonly notated with a small strikethrough circle ø. They are also known as "minor 7th flat 5" chords, also notated as "7b5", and sound very jazzy.
There are four common shapes to this chord. To get the first one, take the diminished chord and move the first note up. The root for this shape is on the A string
Raise the second note to get the next shape. The root for this shape is on the E string.
Let's move the third note up. This half-diminished chord has the root on the G string. This shape is easiest to play by holding fingers 1 and 3 down across the fretboard, while finger 2 pushes down on both of them.
Let's move the fourth note up. This half-diminished chord has the root on the C string.
Minor 6th Chords
The same shape used for half-diminished chords can be used to play minor 6th chords, only that the roots are in different positions, namely a minor third higher than the m7b5 chord root. These chords are often used as the iv6 before the V in a minor progression.
Up next, see how to use the m7b5 chord in a simple progression.
Dominant 9th chords
A quick mention should be given to dominant 9th chords here, which can be played rootless with the same half-diminished shapes. For example, a Cø can serve as F9, with the C serving as 5th, Eb as 7th, G as 9th, and A as the 3rd.
Chord diagrams generated by <uke-chord>