There seems to be a resurgence in analog computer interest. I bought an EAI
TR-20 years ago surplus. It came with extra patch boards but few patch
cables. It's a beast - weighs over 100 pounds but so far I have not used
it. I do have a smaller, lighter "hybrid" Comdyna. It has both an analog
computer and a digital one in the same rack. It weighs a lot less. The
TR-20 will likely need work before powering it up - old capacitors and the
like. The Comdyna is much more recent and works fine though I've only done
some minimal programming for it. I jumpered together an integrator and
differentiator to try things out. This is where having a scope is useful to
look at the output. I have not used the digital side.
Some of these old EAI machines are fetching a surprisingly high price. A
friend of mine has one and he rebuilt the power supply. He also had to
rebuild some of the analog processing modules. He got it working and uses
it as a music synthesizer (though he also has an old Moog and a much less
common Buchla). He had two Moog synths but sold one. One of the first
things he programmed on the TR-20 was a chaos generator. The "waveform" he
generated looked exactly like this:
Well, without the measurements on the waveform.
Steve H.
On Tue, Feb 20, 2024 at 8:49?PM Ed Breya via groups.io <edbreya=
[email protected]> wrote:
I've been sorting out and organizing old project stuff recently, including
documents and parts and whatever. Every couple years or so, I look online
to see if there's anything new going on in certain areas - usually not. I
ran across this stuff now, which looks entirely new, so I have to report on
it. It looks like there's some renewed interest in the good old analog
computer stuff, including modern designs and applications.
Anyway, here's a link to what I think might invigorate the old analog
stuff a bit. Maybe y'all have seen this before, but it's totally new to me.
I've thought about building an analog computer for decades, but never did
it. I finally started a project for this a few years ago, and it will still
likely never be finished, but it's fun to think about.
Enjoy.
Ed
