Switches - experience is a great teacher

 Having worked with this style of keyboard on my last instrument, I was better able to work with this one. 

The organ was in a beach community, so there were a lot of sticky keys. I was able to clean the front bushings and coax the openings a bit wider and the keyboards are beautiful right now. I separated the keyboards from the switches this time. It makes it way easier to work on.  

The swell switch matrix is wired. I used 4 to 5 redundant contacts to make up for the low currents.  Fortunately on this keyboard the springs are already soldered so I don't need to go through that messy process as I did last time. 

Cable dressing on this one, based on experience, is much neater than the last instrument. 

Time to order more ribbon cable...

Tone generators

So it looks like essentially it is the equivalent of a 3 rank highly unified instrument. There were 85 notes of "flute"

73 notes of "diapson"

And 61 notes of "Celeste"

Just inferring from the parts, there is a base sine wave generator for the flute and additional filters for the diapson and celeste

These were on 2 racks with the thousands of wire connections.  You can see the 5 octaves of Celeste, 6 of diapson and 7 of flute. 

I'm glad I live deep into the digital age!!

Old time switching

It is amazing the primitive nature of pre digital designs. 

Key action. 

Pedal key action

Stop action (on the keyboards) and couplers. 

It is all about interconnecting thousands of wires. All done in semiconductor logic now. 

I have always held in admiration the scientists and engineers who were able to create television broadcast and receive systems with a handful of tubes and discrete components.

Opus 3 project - Old analog Rodgers Hauptwerk conversion

An old 70's vintage analog Rodgers came up for sale essentially for transportation cost.  I have been looking to try a conversion of an instrument like this.  These old instruments have pretty good bones, with well built pedalboards and wood core keyboards. 

Transportation was something of a challenge, as I had to get it out of there within a day, and no one was available to help.  However with a combination of our awesome hand truck, working out, a disregard for the finish on the case, removal of most of the interior parts, and judicious application of Newtonian physics, I was able to get it loaded into a pickup myself

This console seems well suited to a conversion.  The contacts on the pedal have multiple contacts, so it looks like I won't have to use reed switches.  The keyboards have some sticky keys, which I'll have to figure out, but they are identical in construction to the old pipe organ keyboards I used in my last project. 

First step was to remove all of the old analog oscillators.  These of course are unusable, and have to go to hazardous waste.  Even being an engineer in the field of electronics development, I'm still stunned by the pace of technology.  This was only 50 years ago!!

There is some additional removal of the now overspecified low efficiency power supply and breakout boards.  Once that's done, I can start work on the keyboards, installing ribbon cables as before.

Stop tabs

I finally got the stop tabs from midiworks. But it was worth it for sure. I spent hours before making cables. This time, plug in a USB cable and you are done. 

I got a 7 port hub from monoprice and mounted it on the stop tab board. On the left is the 2 line display. I added 2 switches to be able to control the combination stepper

Mounting and integration will proceed at the convenience of the owner..

A good home.

The console is in its interim home with a student who can make good use of it. It is compact enough to live in a bedroom!  

I was able to judiciously create backing supports and cut through tenons on the case so that it breaks down into two sides and two supporting back pieces. 

The shell pieces are on the right side of this stack of parts, the stack encompassing the entire console. 

The entire console fit in the back of a pickup, could be moved piece by piece by two people and set up in an upstairs bedroom in less than 30 min. 

I am still waiting on the lighted rocker tab updates, so I have only built the structure to accommodate them, in the promise of later installation. Hopefully by end of September...

AGO standards

I thought I was almost done.  Then I sat down to play, and nothing felt right.  After looking at the AGO specifications. and did some measurements, it was clear why.  The Great was in the wrong place.  I needed to move the entire keyboard stack toward me 3 inches, and down 2 1/2 inches.

After staring at the console shell, the only way I could figure out to do it (without building a new shell, this action being forbidden by my roommate) was to cut the keyboard support out and re-mount it 2 1/2" lower.

This left a rather significant scar on the side.  So out came the sander and black paint.

The bottom of the side panel happened to be 2 1/2 inches lower than the existing keyboard support, so all I needed to do was to add cleats to the bottom,

This placed the keyboards in the right position.

So to summarize, absent of the stoptabs, which hopefully will interface via USB, the MIDI interface of the entire instrument is as follows

with the parts indicated (PEDSCAN, BBS-1K, PDS and MRG2) from www.midi-hardware.com.