what component am I looking for??

[brick]

I am looking for an electronic component and I am having trouble
articulating exactly what it is I want.


** ----------- **
.
`- if any "matter" occupies the space between the **'s,
I get output of some sort.

what are the options?

Thanks

 

[Robert Monsen]

"brick" <joe_furgal@hotmail.com> wrote in message
news:rN98b.934889$ro6.18670136@news2.calgary.shaw.ca...

I am looking for an electronic component and I am having trouble
articulating exactly what it is I want.


** ----------- **
.
`- if any "matter" occupies the space between the **'s,
I get output of some sort.

if the 'matter' casts a shadow, then an opto-interrupter might work. These
are little infrared sender/receiver pairs that have a slot between them that
you can put your 'matter' into.

Regards,
Bob Monsen

what are the options?

Thanks

 

[Walter Harley]

"brick" <joe_furgal@hotmail.com> wrote in message
news:rN98b.934889$ro6.18670136@news2.calgary.shaw.ca...

I am looking for an electronic component and I am having trouble
articulating exactly what it is I want.


** ----------- **
.
`- if any "matter" occupies the space between the **'s,
I get output of some sort.

what are the options?

Difficulty articulating a concept can sometimes be helped by redundancy.
Can you tell us a bit more about what you're trying to achieve?

One idea is to treat the **'s as a capacitor, use the capacitor in an
oscillator circuit, and then detect the frequency. Because different sorts
of matter generally have different dielectric constants than air, they will
cause the capacitance to change, thus changing the oscillator's frequency.

 

[Andrew R Mitz]

proximity detector



Walter Harley (walterh@cafewalter.com) wrote:
: "brick" <joe_furgal@hotmail.com> wrote in message
: news:rN98b.934889$ro6.18670136@news2.calgary.shaw.ca...
: > I am looking for an electronic component and I am having trouble
: > articulating exactly what it is I want.
: >
: >
: > ** ----------- **
: > .
: > `- if any "matter" occupies the space between the **'s,
: > I get output of some sort.
: >
: > what are the options?
:
: Difficulty articulating a concept can sometimes be helped by redundancy.
: Can you tell us a bit more about what you're trying to achieve?
:
: One idea is to treat the **'s as a capacitor, use the capacitor in an
: oscillator circuit, and then detect the frequency. Because different sorts
: of matter generally have different dielectric constants than air, they will
: cause the capacitance to change, thus changing the oscillator's frequency.
:
:

 

[Lizard Blizzard]

Walter Harley wrote:

"brick" <joe_furgal@hotmail.com> wrote in message
news:rN98b.934889$ro6.18670136@news2.calgary.shaw.ca...

I am looking for an electronic component and I am having trouble
articulating exactly what it is I want.


** ----------- **
.
`- if any "matter" occupies the space between the **'s,
I get output of some sort.

what are the options?

Difficulty articulating a concept can sometimes be helped by redundancy.
Can you tell us a bit more about what you're trying to achieve?

One idea is to treat the **'s as a capacitor, use the capacitor in an
oscillator circuit, and then detect the frequency. Because different sorts
of matter generally have different dielectric constants than air, they will
cause the capacitance to change, thus changing the oscillator's frequency.

This is called a proximity detector.

http://www3.telus.net/chemelec/Projects/Proximity-2.htm

http://members.tripod.com/wsimister/prox0699.htm

http://www.discovercircuits.com/S/s-proximity.htm

 

[Lizard Blizzard]

Andrew R Mitz wrote:

proximity detector

[snip]

I haven't seen anything from Andy for what seems like ages.
How's it going?