[sdiy] Synth Keybards and Number of Keys

[John Luciani]

On 3/1/07, Edward King <edwardcking2001 at yahoo.co.uk> wrote:

> Wood (including factory costs to have the wood cut into 2 x sets of 88 keys
> + 4 octaves for spares, mistakes and experimentation)
> =£35
> (& have to mention the company on my website (?!) and if I build more, they
> want me to use them over a competitor)
> + brass bushes = £4
> + 1.5m pivot bar (hardened steel) £0.65
> + galvanised steel chassis (2mm) (factory made) £15
> + 88 x QTC pills (aftertouch sensors) £23
> + bolts (already had an abundance of these)
> + PCB's (have lots of pcb board left over from other projects)
> + Springs (engineering company) £free but I had to fix their network :o)
> + Lever mechanisms (factory made) £5
> + optical switch vanes (factory made) £free, but I have to mention them at
> some point on the website I havent yet found the time to build!!!
> + slotted optical switches (displacement sensing) £65 (bulk purchase)
> + bus bars (2 of, both gold plated) £50
> + felt (upper and lower buffers) £3

That pricing seems quite good considering the volumes.

What does the optical switch vane look like and what slotted optical switch are
you using? Since you are sensing displacement it sounds like you are varying
the amount of light and using an A/D.

I am building a couple of two octave pedal boards that use slotted
optical switches
(PCBs arrive tomorrow!). I am thinking of doing some keyboards that use slotted
optos in an analog mode.

Thanks.

(* jcl *)

-- 
http://www.luciani.org