LDR shoot the moon low ouput

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LDR shoot the moon low ouput

erynforrester
Thanks in advance.
I built a culture jam shoot the moon and used an ldr with the value 40k-140k. Adjusting the trimpot I can get the output almost to unity but it's still too low.
I'm waiting on the right value ldr 5k-500k in the post, wondering if this would effect the output.
Everything else on the pedal works perfect.
Thanks
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Re: LDR shoot the moon low ouput

nocentelli
The gain of the output stage of the shoot the moon trem is set by the resistance between the inverting input and output pin of the output opamp (set by that 10k trimmer) divided by the resistance of the LDR. Since the LDR resistance fluctuates, the output gain fluctuates which gives tremolo. If your LDR will not go below 10k, the output stage cannot go above unity, and with tremolo, unity even at the loudest point of the cycle means that it will still sound quieter than bypass overall. You can install an LDR that gives a lower minium resistance (e.g. if your new LDR drops to 5k, when the trimmer is set to maximum 10k this would give a gain of 10k/5k = x2 gain) OR a simpler solution is to replace the trimmer with a larger value, e.g  47/50k, which would give more scope for boosting the output. If you do both, you will definitely have enough level available to match the effect with unity gain.
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Re: LDR shoot the moon low ouput

erynforrester
Excellent. That was a spectacular explanation. Sounds like I'll be fine once the right value ldr arrives.
Thanks for that