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gary wrote:There are ways around it - see Graham's camera schematics for a nifty nulling arrangement.
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Viewmaster wrote:I haven't seen that nulling.....any link please.
Viewmaster wrote: But one might raise and lower the gain from the light sensor in sync with the AC supply as the volts rises and falls?
Raise the gain when the AC voltage is low and lower the gain when at full volts.
Any good?
Lawnboy wrote:That is actually one thing I forgot to mention. I hooked up a BPW34 photodiode to my oscilloscope to see how bad the lamp flicker from the AC current was, and was pleased to find that it was almost nonexistent, especially when compared to a neon nightlight. I’m sure the 60hz AC frequency helps, but I wont know for sure until I get it built.
gary wrote:Viewmaster wrote:I haven't seen that nulling.....any link please.
V24 #1
Well that's is more or less how it works but it is synced to the mains the same way the camera is - via a light sensor - that way the hum has the characteristics of the light source - don't forget for an incandescent lamp it will be twice the frequency of the mains plus include whatever thermal lag there is.
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