Scalatron technical info

I just picked up an original Scalatron on ebay, but sadly it lacks a
keyboard of any kind. It functions perfectly well (great drones), but
I'd like to build a keyboard for it (or perhaps interface one I
already have). Can anyone tell me how to interface a keyboard?

There are two 1/4" jacks on the back, both of which output audio (one
is amplified and the other is a line out I think). It's pretty funny
how it seems to be built out of a retooled surplus tube TV. The
functional wave viewer is great too (I expected it to just show
presets or something, but it actually displays a real-time black &
white bar view of the wave frequency).

Treen0!

--- In tuning@yahoogroups.com, "treen0" <treen0@...> wrote:
>
> I just picked up an original Scalatron on ebay, but sadly it lacks a
> keyboard of any kind.

That is extraordinary! Hopefully George Secor will see this, as he is
a member of the list but also one of the developers of the Scalatron
George still has a working one, and posts music occasionally. He's a
great guy, too. Good luck!

Cheers,
Jon

this sound like a tuner , not the instrument, still useful!
--
Kraig Grady
North American Embassy of Anaphoria Island <http://anaphoria.com/>
The Wandering Medicine Show
KXLU <http://www.kxlu.com/main.html> 88.9 FM Wed 8-9 pm Los Angeles

--- In tuning@yahoogroups.com, "Jon Szanto" <jszanto@...> wrote:
>
> Treen0!
>
> --- In tuning@yahoogroups.com, "treen0" <treen0@> wrote:
> >
> > I just picked up an original Scalatron on ebay, but sadly it lacks a
> > keyboard of any kind.
>
> That is extraordinary! Hopefully George Secor will see this, as he is
> a member of the list but also one of the developers of the Scalatron
> George still has a working one, and posts music occasionally. He's a
> great guy, too. Good luck!
>
> Cheers,
> Jon
>

Yeah, I found this group by googling Scalatron and excluding all the
stereolab references, which lead me to one of his posts. I'm going to
try to put up a page with pictures and recordings of it in action
sometime soon

--- In tuning@yahoogroups.com, "treen0" <treen0@...> wrote:
>
> I just picked up an original Scalatron on ebay, but sadly it lacks a
> keyboard of any kind. It functions perfectly well (great drones),
but
> I'd like to build a keyboard for it (or perhaps interface one I
> already have). Can anyone tell me how to interface a keyboard?
>
> There are two 1/4" jacks on the back, both of which output audio
(one
> is amplified and the other is a line out I think). It's pretty
funny
> how it seems to be built out of a retooled surplus tube TV. The
> functional wave viewer is great too (I expected it to just show
> presets or something, but it actually displays a real-time black &
> white bar view of the wave frequency).

From your description this has to be a Scalatron tuner. I imagine
that there might be a way to interface a keyboard controller (for one-
note-at-a-time output), but I wouldn't recommend attempting this
unless you're heavily into electronics.

Motorola made two models of the tuner. The older model had the tone
generator (with 1024 tones/octave) and the video display as separate
pieces connected by a 1/4-in. phone cord. Microtonal pitches were
generated by setting various combinations of 10 binary switches,
according to a computer-generated table (in both Hz and cents) that
was included in the instruction manual. I'm not sure if I have a
manual for this version, but I do have the table and an electronic
schematic diagram.

The newer (less expensive) model was consolidated into a single piece
to be marketed to schools. It was considerably less versatile in
that it generated only the pitches of 12-equal (adjustable up or down
in increments of ~4 cents).

The video display for both models consists of a split screen with the
reference pitch (a low-pass filtered square-wave oscillator) at the
left and the live sound (voice or instrument via microphone input) at
the right. As you attempt to match the generated pitch, the display
on the right rolls upward or downward according to whether you're
higher or lower, and you can literally see beats as the bars pass by
one another. (The rolling also stops when your input frequency is a
simple ratio with respect to the generated frequency, e.g., an octave
or just fifth, fourth, twelfth, etc.)

We found that the tuner could be used to evaluate the intonation of a
singer or player in real time using a previously prepared two-track
tape with recorded accompaniment (audible to the player) on one track
and reference pitches recorded from a Scalatron (and patched into the
left channel of the tuner to bypass the internal oscillator) on the
other track. Hearing only the recorded accompaniment, the player
could play along and get instantaneous feedback regarding how closely
the reference pitches were being matched. (And since the reference
pitches were produced on a Scalatron, the music could be microtonal,
providing that the accompaniment was also.) It was not necessary for
the player to memorize the music, because the video display was large
enough to be seen easily with peripheral vision while reading a
printed part -- I know this for a fact, because I tested it myself,
playing a trumpet along with a recorded piano accompaniment.

Sounds pretty nifty, eh?

--George Secor

--- In tuning@yahoogroups.com, "George D. Secor" <gdsecor@...> wrote:
>
> The newer (less expensive) model was consolidated into a single piece
> to be marketed to schools. It was considerably less versatile in
> that it generated only the pitches of 12-equal (adjustable up or down
> in increments of ~4 cents).
>
> The video display for both models consists of a split screen with the
> reference pitch (a low-pass filtered square-wave oscillator) at the
> left and the live sound (voice or instrument via microphone input) at
> the right. As you attempt to match the generated pitch, the display
> on the right rolls upward or downward according to whether you're
> higher or lower, and you can literally see beats as the bars pass by
> one another. (The rolling also stops when your input frequency is a
> simple ratio with respect to the generated frequency, e.g., an octave
> or just fifth, fourth, twelfth, etc.)
>
>
> --George Secor
>

Thanks for the info, from your description I definetely have the
second model. Does this mean that both of the 1/4" jacks on the back
are inputs? They were both outputting sound when I plugged into them.
I'll try using a mic when I get home from work.

I'm a little disappointed that the microtonality of it is less capable
than I'd hoped, but it still sounds like a great VJ/sound analysis tool.

--- In tuning@yahoogroups.com, "treen0" <treen0@...> wrote:
>
> --- In tuning@yahoogroups.com, "George D. Secor" <gdsecor@> wrote:
> >
> > The newer (less expensive) model was consolidated into a single
piece ...
>
> Thanks for the info, from your description I definetely have the
> second model. Does this mean that both of the 1/4" jacks on the back
> are inputs? They were both outputting sound when I plugged into them.

Hmmm, that doesn't seem right. It would make more sense to have both
of the jacks as inputs, since I don't think it had a built-in
microphone (but I may be wrong). I wonder if someone opened the case
and rewired something.

> I'll try using a mic when I get home from work.
>
> I'm a little disappointed that the microtonality of it is less capable
> than I'd hoped,

Yes, I never actually used that model, which is why I don't remember
very much about it. The consolidated tuner/pitch monitor was a last-
ditch attempt by the Scalatron company to generate more sales.

> but it still sounds like a great VJ/sound analysis tool.

I hope you'll be able to figure out how to get a display from an
external source. If it would help, I could send you a schematic of the
two-piece model as a .pdf file.

--George