From: look165@numericable.fr   
      
   A LDR doesn't need power to operate !   
      
   default a écrit le 15/05/2019 à 20:34 :   
   > On Wed, 15 May 2019 20:23:37 +0200, Look165    
   > 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 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 écrit 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 écrit 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   
   >>>   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)