Knobs, Sliders and Switches

Parting out

As you may remember I bought an organ. And now I have a  collection of parts.

For the front panel I now have a few more original Yamaha parts to use and although can't find exactly what I would like, I think I have what I need now.

The Knob-le Art

Last year I decided to buy some original Yamaha knobs. These probably came from a mixer but they are the same as used on the CS-5, 10, 15, 30.

These fit the same knurled shaft potentiometers as used on the SS-30.

They need a bit of clean-up - see below

As I have 12 of these, they will form the bulk of the rotary controls.



The B-75 organ has, sorry, had, a few knobs too, so I have options to use different knobs for different functions.

There are two of these small knobs

One is from a dual-concentric control which was used for Volume/Balance but could be used for Pitch/Detune.

And there are two larger knobs.

Letting Things Slide

The B-75 also has a bunch of slider controls. 

The slider caps are 14x18mm and 11mm high

They also sliders come with these natty covers.

The dimensions are

External 42x19mm
Internal 39.90x16.8mm - for cut-out

opening 28x2.4mm
Slider travel 25mm

inner dimension 36.6x13.3

The tabs are to hold it through a depth of 13.8mm

A possible slider to use with this is: Bourns - PTA2043-2010DPA103 35x9mm, 20mm travel. The original sliders travel is 25mm though. 

This is the main issue with these panel covers - they are quite a small range of travel and I canlt find anything that fits it exactly. The original potentiometers aren't suitabel either, so I might not use them in the end. 

Washing The Pots 

All these old control knobs were a bit grubby, so I gave them a wash.

The New Switcheroo

As noted back in the Attack Formation post I only need switches for the attack control because everything else can be controlled with variable resistors. When I got the organ I was particularly after these switches.

As you can see though, they seem to have had some sort of incident and needed a clean.

In fact the switches were broken. The springs had completed correded.

Luckily the caps come off easily and other switches on eth organ were in fine condition. The desoldering was particularly easy too.

Dimensions 40x14.5

So, I have my attack switches. I didn't wire these up yet but I buzzed the contacts with my multimeter, just in case.

And I also have a power switch