Mikado Analog Sequencer Project

First Posted Feb 3, 2002
Updated 10-8-2007

Main Home Page Link for the Mikado

    Today is 10-8-2007

    I can't believe it has been 5 years since I last worked on this thing.  Here is the current status.

    1. The only existing Mikado (unless somebody else built one while I wasn't looking) is currently broken.  The problem is that the cheap toggle switches I purchased from Jameco have failed, and need to be replaced.

    2. The original also has several hardware bugs.  One is that the original spec called for negative edge triggering on the clock inputs.  I should have questioned that more closely, but didn't.  I have lost the original schematics (I think), but the ones I do have seem to show positive edge triggering...it seems that I may have corrected the schemaitics, but I never wrote down that I did so...ahh....well, that was a very hectic time of my life...I was working for a company that was about to go out of business....

    3.  My goal is to repair the switches (relatively easy) and then re-layout the PC boards so I will have something that will function the way it was supposed to.

    Don't hold your breath.  My life is even a bit more chaotic at the moment...I am in the middle of doing a remodel of my home.

    Today is 8-7-2002

        Progress is good.  Today, I actually hooked it up to my synthesizer (also a homebuilt) and made a short recording.  This probably doesn't sound like much to most, but I need to remind those who don't know me, I don't have much in the way of musical tallent.  If you listen carefully, the patch I am using makes the sequencer skip a step every other time it goes through.  The "percusion" is generated using the patern generator.

     Mikado Demo #1 (~1Meg)

    Here are the latest.

     Picture of the front panel for my system

     Picture of the back of the front panel

     Picture of Board #1 and Board #2

     Picture of a really big helper in this whole project

    The picture of the front panel above you may notice the rather colorful aspect of the banana jacks...well, it turned out a little more colorful that I thought, and while I don't like the way it looks, well, I am too lazy to pull the jacks off and be a little more conservative.  What I had hoped to accomplish was to make it easier for me to figure out which jack did which job....well, I failed....but thems is the breaks.

    And of course, there is a picture of my little helper...he sure made doing the project interesting...and he even added a bit to the paint job on the panel.

    This is a project that I am doing with Jim Johnson.  It is a pretty involved circuit that is basically an analog sequencer on steroids.

    The plan has been changed just a little bit.  To save time, I have ended up putting the sequencer on three boards.

    Board #1 contains the 8x2 sequencer and the quantizer.  To make the full system, you will need two of these cards.

    Board #2 Contains the Midi Interface, Master Clock, the Dividers, and Logic.

    Board #3 Contains the Patern Generator, Analog Switches, One Shot, Transposer and Power Supply.

    The current status is that the boards should go out for a prototype run near the end of April.  The plan is for the first prototype unit to be completed by the end of May.

Program to generate quantizing tables

    You will find that in the current version, there are a few things that do anything.  Like File Load, Save As.  File save will cause the program to generate a rom image for a 27C010 in the file quan.bin.  This program is for Windows.  It was compiled with Borland C++ Version 4.52.

     Quantizer Look Up Table Generator (Includes Source)


    See ya all later...