Coils

Michael Black wrote:
On Mon, 30 Jan 2012, Winston wrote:

(...)

And see how this guy uses a cheap calculator
as a turns counter?! Genius!

That sort of thing wasn't uncommon 35 years ago, once there were cheap calculators.
One could also use a pedometer, now  made cheap since they've become faddish, and

 > thus available in cereal and garage sales.

I bought a couple for just that use. Unfortunately they stop working
properly at lower battery voltage and the 'calculator' solution yields
a unit with a larger display anyway.

Of course, one could just strip an old cassette deck, and use the counter from that, so long as one could properly
connect it to the rest of the mechanism.

Thassa lot of work.  I'd go as far as putting an opto interrupter
wired across the "=" key of a dollar store calculator but not
much more.  :)

--Winston

On Jan 30, 7:09 pm, Winston<Wins...@Bigbrother.net> wrote:
Michael Black wrote:
On Mon, 30 Jan 2012, Winston wrote:

(...)

And see how this guy uses a cheap calculator
as a turns counter?! Genius!

That sort of thing wasn't uncommon 35 years ago, once there were cheap calculators.
One could also use a pedometer, now made cheap since they've become faddish, and

thus available in cereal and garage sales.

I bought a couple for just that use. Unfortunately they stop working
properly at lower battery voltage and the 'calculator' solution yields
a unit with a larger display anyway.

Of course, one could just strip an old cassette deck, and use the counter from that, so long as one could properly
connect it to the rest of the mechanism.

Thassa lot of work. I'd go as far as putting an opto interrupter
wired across the "=" key of a dollar store calculator but not
much more. :)

--Winston

A colleague made a magnetic quadrature counter that could do
direction....
which is nice if you want to take a few turns off.
(Hall sensors and two magnets)


The electronics were made for a different signal.
http://www.teachspin.com/instruments/moderni/experiments.shtml#die

You get four counts per revolution.

On Sat, 28 Jan 2012 06:32:06 -0500, Michael A. Terrell wrote:

snip


http://www.lindsaybks.com/dgjp/djgbk/coil/index.html

This is great. I'm familiar with Lindsay - I've gotten books from them
before. Thank you for this link.

Jasen Betts wrote:
On 2012-01-27, Winston<Winston_at_Bigbrother.net> wrote:
George Herold wrote:

See how he's adapted a cable to allow foot
control of the motor speed?

As soon as I saw that I thought "Coil Winder"!

mount a chuck on the back wheel of a domestic sewing machine,

And see how this guy uses a cheap calculator
as a turns counter?! Genius!

George Herold wrote:
On Jan 30, 7:09 pm, Winston<Wins...@Bigbrother.net>  wrote:
Michael Black wrote:
On Mon, 30 Jan 2012, Winston wrote:

(...)

And see how this guy uses a cheap calculator
as a turns counter?! Genius!

That sort of thing wasn't uncommon 35 years ago, once there were cheap calculators.
One could also use a pedometer, now  made cheap since they've become faddish, and

  >  thus available in cereal and garage sales.

I bought a couple for just that use. Unfortunately they stop working
properly at lower battery voltage and the 'calculator' solution yields
a unit with a larger display anyway.

Of course, one could just strip an old cassette deck, and use the counter from that, so long as one could properly
connect it to the rest of the mechanism.

Thassa lot of work.  I'd go as far as putting an opto interrupter
wired across the "=" key of a dollar store calculator but not
much more.  :)

--Winston

A colleague made a magnetic quadrature counter that could do
direction....
which is nice if you want to take a few turns off.
(Hall sensors and two magnets)

The electronics were made for a different signal.
http://www.teachspin.com/instruments/moderni/experiments.shtml#die

You get four counts per revolution.

Wow! I was just getting used to the ultra-fine divisions in regular
encoder wheels and you show me an apparatus with sub-wavelength
resolution!  Incredible!

--Winston- Hide quoted text -

- Show quoted text -

On Jan 31, 12:05 am, Winston<Wins...@Bigbrother.net> wrote:

Wow! I was just getting used to the ultra-fine divisions in regular
encoder wheels and you show me an apparatus with sub-wavelength
resolution! Incredible!

--Winston- Hide quoted text -

- Show quoted text -

Grin... sure but it costs a bit more than an encoder wheel.

Each count is 1/8th of the wavelength, less than 100nm... does that
count as nanotech? :^)
What I hadn't known about the quadrature technique is that the (phase)
noise stays all on the 'rim' of the circle. I guess that's 'obvious'
in retrospect.