Shrinking Lumazoid to a micro board

[Drizzt321]

So I’m going to be shrinking down the Lumazoid to fit into a smaller space based on a Arduino Pro Mini (328p, https://www.sparkfun.com/products/11113). For the POTs, are they regular 10K POTs? So I can use a smaller trimpot as long as it’s 10K?

Either that or I’ll have to re-write that bit of the code to use momentary buttons to increment/decrement or loop through the possible settings. Doable if I have time, but I may end up not.

I believe I won’t need the oscillator or power circuitry stuff as that’s already on the mini board, likewise most of the audio jacks stuff since I’m going to use an electret mic. Would I still need the R4 and C7? Using an adjustable gain mic like https://www.amazon.com/gp/product/B00K9M6S1O

[Michael]

Yes, the pots are 10K, and trimpots will work, but I have found cermet trimpots to have much less “resolution” and values jump around a lot. They don’t have a smooth transition of resistance like a larger pot.

If your audio input only has 1 channel, then you don’t need the summing circuit (R4, R5). You do need C7, as this capacitor blocks DC current.

[Drizzt321]

Thanks Michael.

I have the proper 10uF ceramic cap on the way, I’ll get it today and test out the audio signal. Good to know the 4.7K resistors aren’t needed.

So the pots are linear? Would you say https://www.amazon.com/MCIGICM-potentiometer-assortment-Breadboard-Potentiometer/dp/B07C3XHVXV would work well and properly? Since the trimpots I got (such as these ones https://www.amazon.com/Variable-Resistor-Trimmer-Potentiometer-Assorted/dp/B07J4NR372) seem to work OK for updating the settings, but clearly not effective for the fine tuning during regular running.

[Michael]

Yes, the pots are linear. Yes, those trimpots will work well enough. They are cermet pots, which like I said are not as precise and smooth, but it will be fine.

[Author]

Posts