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Request Data for Mellotron Motor

Request Data for Mellotron Motor

2011-09-28 by arcsound

I have a pair of M400s that have the original motor drive boards.  They are in storage, but I would like to start restoring them now.  One thing I would like to do is replace the motor drive board with something that does not sag, i.e. will support a couple of fistful of notes without slowing down.  Does anyone have any data on the correct voltage range and the typical current draws for different numbers of simultaneous notes?  There are a number of DC motor controllers on the market for industrial applications, and I'm hoping to find one to match up with the Tron's needs. 

best,
Richard
Troy, VA

Re: [Mellotronists] Request Data for Mellotron Motor

2011-09-28 by Ken Leonard

I'm not able to help with the numbers, but maybe you can measure the
controllers you have now to get a ballpark?

Generally folks get an SMS-2 from Streetly or SMS-5 from Mellotron
Archives.  These aren't cheap, and they require a bit of rewiring to
get them installed, but they work well.  The SMS-5 has a high/low
speed option you can toggle while playing (think half-speed brass).

Usually the SMS controllers are "customer installable" if you know
your way around a soldering iron, provided that your power supply is a
standard one.  Some power supplies--few, fortunately--aren't quite
normal and require slightly different wiring.  Streetly or Mellotron
Archives can help you out with that.  I ran into one of those once
long ago, but it was quickly sorted out by moving a wire or two
(sorry, I forget the details).

Now that you mention a DIY approach, has anyone ever considered
revving up an Arduino to sense the pulses from the tach head and
supply an apt voltage to the motor?  Ya know, that might be
interesting (and way beyond my capabilities :-) ).

...kl...

On Wed, Sep 28, 2011 at 11:28 AM, arcsound <arcsound@...> wrote:
> I have a pair of M400s that have the original motor drive boards.  They are in storage, but I would like to start restoring them now.  One thing I would like to do is replace the motor drive board with something that does not sag, i.e. will support a couple of fistful of notes without slowing down.  Does anyone have any data on the correct voltage range and the typical current draws for different numbers of simultaneous notes?  There are a number of DC motor controllers on the market for industrial applications, and I'm hoping to find one to match up with the Tron's needs.

Re: [Mellotronists] Request Data for Mellotron Motor

2011-09-28 by lsf5275@aol.com

The Arduino seems interesting. I had never heard of it but I am interested  
to learn more and see if it can be applied as a tool to assist me in  my 
various undertakings. I wonder if its architecture could be adapted to  pitch 
control. Can it measure and control and at the same time be manipulated.  
Interesting idea.
 
 
In a message dated 9/28/2011 1:25:12 P.M. Eastern Daylight Time,  
ken@... writes:

 
 
 
I'm not able to help with the numbers, but maybe you can measure  the
controllers you have now to get a ballpark?

Generally folks get  an SMS-2 from Streetly or SMS-5 from Mellotron
Archives. These aren't  cheap, and they require a bit of rewiring to
get them installed, but they  work well. The SMS-5 has a high/low
speed option you can toggle while  playing (think half-speed brass).

Usually the SMS controllers are  "customer installable" if you know
your way around a soldering iron,  provided that your power supply is a
standard one. Some power  supplies--few, fortunately--aren't quite
normal and require slightly  different wiring. Streetly or Mellotron
Archives can help you out with  that. I ran into one of those once
long ago, but it was quickly sorted out  by moving a wire or two
(sorry, I forget the details).

Now that you  mention a DIY approach, has anyone ever considered
revving up an Arduino to  sense the pulses from the tach head and
supply an apt voltage to the motor?  Ya know, that might be
interesting (and way beyond my capabilities :-)  ).

...kl...

On Wed, Sep 28, 2011 at 11:28 AM, arcsound <_arcsound@..._ 
(mailto:arcsound@...) >  wrote:
> I have a pair of M400s that have the original motor drive  boards.  They 
are in storage, but I would like to start restoring them  now.  One thing I 
would like to do is replace the motor drive board with  something that does 
not sag, i.e. will support a couple of fistful of notes  without slowing 
down.  Does anyone have any data on the correct voltage  range and the typical 
current draws for different numbers of simultaneous  notes?  There are a 
number of DC motor controllers on the market for  industrial applications, and 
I'm hoping to find one to match up with the  Tron's needs.

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