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whisky-dave[_2_] whisky-dave[_2_] is offline
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Default small potentiomenter with switch

On Friday, 23 April 2021 at 23:14:34 UTC+1, Rod Speed wrote:
"whisky-dave" wrote in message
On Friday, 23 April 2021 at 21:11:43 UTC+1, Peter Able wrote:
On 23/04/2021 11:31, whisky-dave wrote:
On Wednesday, 21 April 2021 at 19:42:11 UTC+1, Peter Able wrote:
On 21/04/2021 13:29, whisky-dave wrote:
On Wednesday, 21 April 2021 at 12:18:47 UTC+1, Peter Able wrote:
On 20/04/2021 22:17, whisky-dave wrote:
On Tuesday, 20 April 2021 at 20:09:11 UTC+1, Peter Able wrote:
On 20/04/2021 11:47, whisky-dave wrote:
Does anyone know where I can buy those old school type small
potentiomenter with switch you know the ones like they had on the
first hand held radios in the 60s-70s and on walkmans and stuff
just a little wheel and the click for volume control. And cheap
of course

I know I could by the standard rather large pots with DSPT but I
want to put
this thing inside a mouse (computer mouse that is) .

Get one out of a scrap radio is the literal answer.

Tell us about the mouse project !

It's for a small project to get students (those interested in
hardware) to adapt an old mouse or we can supply one
so they can have rapid fire button with speed adjust. So need to
switch it off for normal use too.
unfortunately these seem more expensive (over £3) than the mice we
buy ;-)

yes I know there maybe a software solution but we need to attract
more than just keyboard kiddies to hardware.

looking to buy 20-40

Respect! That's a brilliant project.

"thumbwheel potentiometer switch" produces 25 10k log taper for
£30 on ebay.

Hope you don't need LINear. !


Cheers althouth TBA these type may be a problem mounting on a mouse.
Currently using a finger preset

Although it appears just adjusting the frequence of a 555 or the M/S
ratio doesn;t give a very good range.
Seem both frequency and M/S may need tweeking which is a pain.

now need to find a small , cheap, round mount hole switch.

We try to run 4 or 5 of these type activities a year for students
they aren't marked or compulsary
just a fun activity but the days of using a LED , 555 based egg timer
are well gone.
Need to think of something that can't be done on a phone or watch and
students can show off to friends.

Good luck then.

Incidentally you could probably do what you want to do with two small
press or touch switches - and a microcontroller. Shoving your students
in at the deep end, I guess - but it could be a forward-looking

Far to advanced and difficult to do., due to size restriction.
These are 1st year students even final year students would have
problems with that.

And it could then simulate LOG, LIN, Ballistic or whatever.

No point as the interface on the computer wouldn't see that effect.

And make LEDs flash !

No that's more like it. :-)

You might be surprised!

I'm sure you'd be more surprised by the level our student tend to be ;-)

s When I was at University - late 60s -

In those days the bright went to university,

Not just those, the more stupid trained to be teachers there.

It depended on where their interest were, a few of our ex students are now lectures,
one became head of department.

now it is more for those that can't get a job after leaving school.


We get a quite a few from "Clearing" which is those that have failed to get into their preferred
courses they have applied to study, so they lack the relatively high grades in physics and maths
that are needed so fall behind.

seemed to have heard of devices with more than four pins - and the idea
of system engineering was unheard of. I broke the mould with a mass of

TTL ! the first chips I can across were DTL when working as a school

The first I used was RTL.

Still a step up from valves

but the thing everyone came in the lab to be hypnotised by was a
relatively simple pseudo binary sequencer used to try to break the main
design. It ran at many megabits per second, but I included four
Lilliput bulbs driven by certain bits of the pbs, but only updated every

A real crowd puller!

Well this is why we are trying to find activities that get their interest
and put their smartphones away.