MOTM

In a message dated 2/12/2000 5:52:29 PM, jlarryh@... writes:

>> Though, installing my old radio in my "new" truck may
>> cause me to increase my (alcohol) consumption substantially.

>Duct tape it under that dash like a real man !

The dash was the simple part. Mounting the antenna and running the antenna 
and speaker cable (not to mention installing speakers) through the double 
steel wall kick panels without going through some unfortunate part is the 
main draw back. I may just drill a bunch of holes and do a bunch of patching 
with an extra large tube of silicone -- the stuff must have some uses outside 
of Hollywood.
 

>> >P.S.  That joystick panel is my next drillin' project.

>> I'd be very interested to hear what this panel is about, and how it
>develops.

>Well, you and I have discussed this before.  But, essentially, there will
>be four pots in MOTM spacing fashion across the top two rows.  Below that
>will be the joystick, sticking straight out.  Below that will be 4 jacks
>along the bottom row. (2 unit panel of course).

Interesting physical layout! I've mentioned the old scrap computer joysticks 
(which would allow them to be moved to left-hand keyboard uses for standard 
pitch bend and modulation uses) but actually mounting them on a module is a 
good idea as well.

>The controls will be X - gain and Y - gain to control the output voltage
>range and X trim (or offset) and Y trim to adjust the DC output to zero
>(or
>some other voltage) when the joystick is in its center resting position.

>The output jacks will be X +    X -    Y + and Y -.  I intend to use simple
>op-amps to buffer the output and provide inversion.  So, joystick movement
>will produce positive going and negative going voltages at the same time
>(equal and opposite).

>That's pretty much the plan.

Sounds like a great plan! Let us know how this goes, maybe I'll get my ass in 
gear to do something similar.

Glad you liked the VC EG idea!
JB

> From: JWBarlow@...
> 
> Interesting physical layout! I've mentioned the old scrap
> computer joysticks  (which would allow them to be moved
> to left-hand keyboard uses for standard pitch bend and 
> modulation uses) but actually mounting them on a module
> is a good idea as well.

Well, I am not sure it is such a good idea, and it certainly is not
original.  But, I have seen something similar on some other modular photos
and thought it would be fun.  Plus, I have been looking for some simple DIY
stuff I could do to help me with the learning of basic op-amp circuits. 
This one looks like it would be hard to screw up even for a stooge like me.
 And, I have these two perfectly good and quite nice looking joysticks I
bought surplus (one for the project, and one for a spare part).  They are
slightly larger that the typical keyboard joystick (maybe twice as big). 
But, based on the button on top, I would say they were "game" oriented.  I
thought about all the cool things I could do with the joystick button, and
finally decided on a rather mundane task.  If I can figure it out, when
depressed, the button would take all 4 output voltages to zero.  This would
make it easy to "trim" the offset to zero by ear, and it might make a cool
effect button to toggle back and forth between the stick position output
voltage an zero rapidly.

My challenge is that my joystick pot is not as large as I would have
preferred.  Therefore, to keep the current at a minimum in the voltage
divider, I will need to have some gain in one of my op amp stages to get
the kind of output range I was looking for.  Oh well, looks like my
learning opportunities just increased.
 
> Sounds like a great plan! Let us know how this goes, maybe
> I'll get my ass in gear to do something similar.

Well, I have to FIND time to do it first.  It crossed my mind again
yesterday whilst drilling that multiple panel.  cutting the joystick hole
with hand tools will be a challenge.  I have some MOTM blank panels.  And,
I even have a proto-board kit.  However, I think I will save the proto
board kit for something a little more elaborate.  This one should have only
one or two chips and a handful of resistors.  I'll probably get a smaller
project board.
 
> Glad you liked the VC EG idea!

Yep, really cool.  More than anything, your description helped "turn the
light on" for me upstairs to understand how I might use a VC EG.  Being the
"modular-stupid" stooge of the group, sometimes I have to ask "WHY?" when
others in the group ask Paul for this and that.  So, every new
understanding of HOW I would use a certain feature musically is a great
benefit.

Larry Hendry