From: scientist77017@gmail.com   
      
   On Saturday, May 18, 2019 at 1:03:05 PM UTC-5, Cursitor Doom wrote:   
   > On Sat, 18 May 2019 10:50:16 -0700, AK wrote:   
   >    
   > > So it looks like even with a laser shining and someone breaks the beam,   
   > > it may not sound if the light level is high enough.   
   >    
   > Dump the LDR and use a photodiode instead.   
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   Would this work?   
      
   Silicon Photodiode with Daylight Filter   
   PIN Photodiode Chip, BPW34   
   Features   
   Photocurrent: 80 µA (? 50 µA)   
   Reverse voltage: 32V   
   Forward voltage @ current: 1.3V @ 80uA   
   Total power dissipation: 150mW   
   Spectral sensitivity: 0.62 A/W   
   Wavelength of max. sensitivity: 850nm   
   Radiant sensitive area: 7.0mm²   
   Half angle: ±60 degrees   
   Short switching time: 20ns typ.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)