[Laser] OPT101 and audio amplifier

[Steve J. Noll]

Roger that.  FWIW when at work at Advanced Photonix doing photodiode 
measurements with a lock-in amp we modulated the light signal at 17 Hz.
That avoided 60 Hz and any harmonic or sub-harmonic of it. Result is 
ability to make accurate measurements of infinitesimally tiny signals.

73, Steve WA6EJO


On 8/12/2016 2:11 PM, Zack Widup wrote:
> Flicker from fluorescent lights is twice the AC frequency of 60 Hz.
>
> 73, Zack W9SZ
>
>
> On Fri, Aug 12, 2016 at 4:03 PM, Alvaro de Leon Romo <xe2at at hotmail.com>
> wrote:
>
>> Whats produce the 120hz interference ??
>> XE2AT
>>
>> Enviado desde mi HTC de Telcel
>>
>> ----- Mensaje de respuesta -----
>> De: "Mike Long" <mike at milisake.com>
>> Para: "Free Space LASER Communications" <laser at mailman.qth.net>
>> Asunto: [Laser] OPT101 and audio amplifier
>> Fecha: vie., ago. 12, 2016 15:56
>>
>> Thanks for the confirmation Steve.  I agree, if I were using it outside of
>> the demonstration then there is much more that should be done to optimize
>> it. Just doing this should hopefully peak a few people's interest in the
>> area.
>>
>> 73,
>> Mike
>> W6RP
>>
>> On Fri, Aug 12, 2016 at 3:44 PM, Steve J. Noll <sjnoll at ix.netcom.com>
>> wrote:
>>
>>> Should work fine. I would want a blocking cap between the OPT101 and the
>>> audio amp as the OPT101 will have a large DC output from ambient light.
>>> Going further you could insert a filter to reduce the 60 Hz and 120 Hz
>>> interference.
>>>
>>> 73, Steve WA6EJO
>>>