Resistance Light and Dark Values

[default]

On Wed, 15 May 2019 16:01:04 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

On 5/15/19 2:34 PM, default wrote:
On Wed, 15 May 2019 20:23:37 +0200, Look165 <look165@numericable.fr
wrote:

A bad friend which act only in one way !

No problem, stick two back to back.

When do you actually need bidirectional conduction? Audio or linear
applications maybe, that's about it, and he's just looking for on-off
control here.

Phil Hobbs a écrit le 15/05/2019 ŕ 20:05 :
On 5/15/19 1:26 PM, Look165 wrote:
For an alarm, do you care to 10ms for instance ?

Phil Hobbs a écrit le 15/05/2019 ŕ 19:20 :
On 5/15/19 1:14 PM, Look165 wrote:
Yes, it can.
A photodiode takes time to turn on or off, about the same a LDR takes.
LDR are reversible, standard photodiodes are only one way.

Cursitor Doom a écrit le 15/05/2019 ŕ 16:30 :
On Wed, 15 May 2019 11:15:18 +0200, Look165 wrote:

A LDR reacts in some ms when the light's  wavelength is in the
operating
range.
You really can't beat a photodiode, though.





A fast photodiode will respond in picoseconds.  Even slow ones are in
the tens-of-nanosecond range if used with the right transimpedance amp.

They're also highly linear and stable, neither of which is true of CdS
cells.

Cheers

Phil Hobbs

Of course not, but you gave Bad Info about photodiodes, who are sort of
friends of mine.

Cheers

Phil Hobbs


Would everyone please quit top-posting?

OK

I think you mean "antiparallel" or "inverse parallel". "Back-to-back"
means inverse series, as in "back-to-back zeners".

Point taken. How's about 69?
Cheers

Phil Hobbs

 

[Phil Hobbs]

On 5/15/19 2:55 PM, Look165 wrote:

A LDR doesn't need power to operate !

default a Êcrit le 15/05/2019 à 20:34 :
On Wed, 15 May 2019 20:23:37 +0200, Look165 <look165@numericable.fr
wrote:

A bad friend which act only in one way !
No problem, stick two back to back.

When do you actually need bidirectional conduction?  Audio or linear
applications maybe, that's about it, and he's just looking for on-off
control here.
Phil Hobbs a Êcrit le 15/05/2019 à 20:05 :
On 5/15/19 1:26 PM, Look165 wrote:
For an alarm, do you care to 10ms for instance ?

Phil Hobbs a Êcrit le 15/05/2019 à 19:20 :
On 5/15/19 1:14 PM, Look165 wrote:
Yes, it can.
A photodiode takes time to turn on or off, about the same a LDR
takes.
LDR are reversible, standard photodiodes are only one way.

Cursitor Doom a Êcrit le 15/05/2019 à 16:30 :
On Wed, 15 May 2019 11:15:18 +0200, Look165 wrote:

A LDR reacts in some ms when the light's  wavelength is in the
operating
range.
You really can't beat a photodiode, though.





A fast photodiode will respond in picoseconds.  Even slow ones are in
the tens-of-nanosecond range if used with the right transimpedance
amp.

They're also highly linear and stable, neither of which is true of
CdS
cells.

Cheers

Phil Hobbs

Of course not, but you gave Bad Info about photodiodes, who are sort of
friends of mine.

Cheers

Phil Hobbs

Really? A lot of renewable energy is supplied by big photodiodes (aka
solar cells). All an unpowered LDR does is sit there.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Phil Hobbs]

On 5/15/19 2:34 PM, default wrote:

On Wed, 15 May 2019 20:23:37 +0200, Look165 <look165@numericable.fr
wrote:

A bad friend which act only in one way !

No problem, stick two back to back.

When do you actually need bidirectional conduction? Audio or linear
applications maybe, that's about it, and he's just looking for on-off
control here.

Phil Hobbs a Êcrit le 15/05/2019 à 20:05 :
On 5/15/19 1:26 PM, Look165 wrote:
For an alarm, do you care to 10ms for instance ?

Phil Hobbs a Êcrit le 15/05/2019 à 19:20 :
On 5/15/19 1:14 PM, Look165 wrote:
Yes, it can.
A photodiode takes time to turn on or off, about the same a LDR takes.
LDR are reversible, standard photodiodes are only one way.

Cursitor Doom a Êcrit le 15/05/2019 à 16:30 :
On Wed, 15 May 2019 11:15:18 +0200, Look165 wrote:

A LDR reacts in some ms when the light's  wavelength is in the
operating
range.
You really can't beat a photodiode, though.





A fast photodiode will respond in picoseconds.  Even slow ones are in
the tens-of-nanosecond range if used with the right transimpedance amp.

They're also highly linear and stable, neither of which is true of CdS
cells.

Cheers

Phil Hobbs

Of course not, but you gave Bad Info about photodiodes, who are sort of
friends of mine.

Cheers

Phil Hobbs

Would everyone please quit top-posting?

I think you mean "antiparallel" or "inverse parallel". "Back-to-back"
means inverse series, as in "back-to-back zeners".

Cheers

Phil Hobbs

 

[Phil Hobbs]

On 5/15/19 2:23 PM, Look165 wrote:

A bad friend which act only in one way !

Phil Hobbs a Êcrit le 15/05/2019 à 20:05 :
On 5/15/19 1:26 PM, Look165 wrote:
For an alarm, do you care to 10ms for instance ?

Phil Hobbs a Êcrit le 15/05/2019 à 19:20 :
On 5/15/19 1:14 PM, Look165 wrote:
Yes, it can.
A photodiode takes time to turn on or off, about the same a LDR takes.
LDR are reversible, standard photodiodes are only one way.

Cursitor Doom a Êcrit le 15/05/2019 à 16:30 :
On Wed, 15 May 2019 11:15:18 +0200, Look165 wrote:

A LDR reacts in some ms when the light's  wavelength is in the
operating
range.
You really can't beat a photodiode, though.





A fast photodiode will respond in picoseconds.  Even slow ones are in
the tens-of-nanosecond range if used with the right transimpedance amp.

They're also highly linear and stable, neither of which is true of CdS
cells.

Cheers

Phil Hobbs

Of course not, but you gave Bad Info about photodiodes, who are sort of
friends of mine.

Cheers

Phil Hobbs

Along with a lot of other stuff, they've been paying my bills since
1983ish. Friends don't come a lot more faithful than that.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[default]

On Wed, 15 May 2019 20:55:41 +0200, Look165 <look165@numericable.fr>
wrote:

>A LDR doesn't need power to operate !

Actually it does. It does not generate any power and is dependent on
some outside power before it's resistance change can do anything.

Photo diodes can produce current when subjected to light, LED's ditto.

Is this all news to you? are you just being obstreperous?

I saw one optocoupler datasheet that uses a series string of
integrated photo diodes to produce the voltage necessary to bias a
mosfet on... here it is:

http://www.bristolwatch.com/ele2/mosfet_relay/x1.png

Now, do you want to rethink the idea that they need power?

default a écrit le 15/05/2019 ŕ 20:34 :
On Wed, 15 May 2019 20:23:37 +0200, Look165 <look165@numericable.fr
wrote:

A bad friend which act only in one way !
No problem, stick two back to back.

When do you actually need bidirectional conduction? Audio or linear
applications maybe, that's about it, and he's just looking for on-off
control here.
Phil Hobbs a écrit le 15/05/2019 ŕ 20:05 :
On 5/15/19 1:26 PM, Look165 wrote:
For an alarm, do you care to 10ms for instance ?

Phil Hobbs a écrit le 15/05/2019 ŕ 19:20 :
On 5/15/19 1:14 PM, Look165 wrote:
Yes, it can.
A photodiode takes time to turn on or off, about the same a LDR takes.
LDR are reversible, standard photodiodes are only one way.

Cursitor Doom a écrit le 15/05/2019 ŕ 16:30 :
On Wed, 15 May 2019 11:15:18 +0200, Look165 wrote:

A LDR reacts in some ms when the light's  wavelength is in the
operating
range.
You really can't beat a photodiode, though.





A fast photodiode will respond in picoseconds.  Even slow ones are in
the tens-of-nanosecond range if used with the right transimpedance amp.

They're also highly linear and stable, neither of which is true of CdS
cells.

Cheers

Phil Hobbs

Of course not, but you gave Bad Info about photodiodes, who are sort of
friends of mine.

Cheers

Phil Hobbs

 

[Phil Hobbs]

On 5/15/19 4:06 PM, default wrote:

On Wed, 15 May 2019 16:01:04 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 5/15/19 2:34 PM, default wrote:
On Wed, 15 May 2019 20:23:37 +0200, Look165 <look165@numericable.fr
wrote:

A bad friend which act only in one way !

No problem, stick two back to back.

When do you actually need bidirectional conduction? Audio or linear
applications maybe, that's about it, and he's just looking for on-off
control here.

Phil Hobbs a Êcrit le 15/05/2019 à 20:05 :
On 5/15/19 1:26 PM, Look165 wrote:
For an alarm, do you care to 10ms for instance ?

Phil Hobbs a Êcrit le 15/05/2019 à 19:20 :
On 5/15/19 1:14 PM, Look165 wrote:
Yes, it can.
A photodiode takes time to turn on or off, about the same a LDR takes.
LDR are reversible, standard photodiodes are only one way.

Cursitor Doom a Êcrit le 15/05/2019 à 16:30 :
On Wed, 15 May 2019 11:15:18 +0200, Look165 wrote:

A LDR reacts in some ms when the light's  wavelength is in the
operating
range.
You really can't beat a photodiode, though.





A fast photodiode will respond in picoseconds.  Even slow ones are in
the tens-of-nanosecond range if used with the right transimpedance amp.

They're also highly linear and stable, neither of which is true of CdS
cells.

Cheers

Phil Hobbs

Of course not, but you gave Bad Info about photodiodes, who are sort of
friends of mine.

Cheers

Phil Hobbs


Would everyone please quit top-posting?

OK

I think you mean "antiparallel" or "inverse parallel". "Back-to-back"
means inverse series, as in "back-to-back zeners".

Point taken. How's about 69?

Nah, that's too exciting a hobby. Electronics you can do for hours and
hours.

Cheers

Phil Hobbs

 

[George Herold]

On Wednesday, May 15, 2019 at 3:59:27 PM UTC-4, Phil Hobbs wrote:

On 5/15/19 2:23 PM, Look165 wrote:
A bad friend which act only in one way !

Phil Hobbs a Êcrit le 15/05/2019 à 20:05 :
On 5/15/19 1:26 PM, Look165 wrote:
For an alarm, do you care to 10ms for instance ?

Phil Hobbs a Êcrit le 15/05/2019 à 19:20 :
On 5/15/19 1:14 PM, Look165 wrote:
Yes, it can.
A photodiode takes time to turn on or off, about the same a LDR takes.
LDR are reversible, standard photodiodes are only one way.

Cursitor Doom a Êcrit le 15/05/2019 à 16:30 :
On Wed, 15 May 2019 11:15:18 +0200, Look165 wrote:

A LDR reacts in some ms when the light's  wavelength is in the
operating
range.
You really can't beat a photodiode, though.





A fast photodiode will respond in picoseconds.  Even slow ones are in
the tens-of-nanosecond range if used with the right transimpedance amp.

They're also highly linear and stable, neither of which is true of CdS
cells.

Cheers

Phil Hobbs

Of course not, but you gave Bad Info about photodiodes, who are sort of
friends of mine.

Cheers

Phil Hobbs


Along with a lot of other stuff, they've been paying my bills since
1983ish. Friends don't come a lot more faithful than that.

It's terrible PC-wise to say, but it's important to be
biased when it comes to photodiodes. :^)

George H.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Phil Hobbs]

On 5/16/19 8:12 PM, George Herold wrote:

On Wednesday, May 15, 2019 at 3:59:27 PM UTC-4, Phil Hobbs wrote:
On 5/15/19 2:23 PM, Look165 wrote:
A bad friend which act only in one way !

Phil Hobbs a Êcrit le 15/05/2019 à 20:05 :
On 5/15/19 1:26 PM, Look165 wrote:
For an alarm, do you care to 10ms for instance ?

Phil Hobbs a Êcrit le 15/05/2019 à 19:20 :
On 5/15/19 1:14 PM, Look165 wrote:
Yes, it can.
A photodiode takes time to turn on or off, about the same a LDR takes.
LDR are reversible, standard photodiodes are only one way.

Cursitor Doom a Êcrit le 15/05/2019 à 16:30 :
On Wed, 15 May 2019 11:15:18 +0200, Look165 wrote:

A LDR reacts in some ms when the light's  wavelength is in the
operating
range.
You really can't beat a photodiode, though.





A fast photodiode will respond in picoseconds.  Even slow ones are in
the tens-of-nanosecond range if used with the right transimpedance amp.

They're also highly linear and stable, neither of which is true of CdS
cells.

Cheers

Phil Hobbs

Of course not, but you gave Bad Info about photodiodes, who are sort of
friends of mine.

Cheers

Phil Hobbs


Along with a lot of other stuff, they've been paying my bills since
1983ish. Friends don't come a lot more faithful than that.
It's terrible PC-wise to say, but it's important to be
biased when it comes to photodiodes. :^)

You only say that because you're a man.

Cheers

Phil Hobbs


--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com