In case anybody should mistake me for an expert, I was wrong. Others have suggested excellent ideas, which have been turned into working projects, so please ignore my amateur suggestion.
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Hey that fan idea was pretty cool, it’s just not a transistor. 
But in the video it’s also an ldr. I will probably try it but i think i need a fan large enough so it can cover an uncover the entire ldr. It’s on an octal tube socket so it’s about 3-4cm in diameter
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Ok so i have these daven .02% tolerance resistors.
10x 8k
6x 40k
I cannot really verify them because my meters are probably not 0.02% acurate. Anyway 10 seems like a useful number.
Also the mica sheet resistors look really coon but can’t find any information on it. They all measure around 1.6k on my cheap multimeter and also on the cheap component tester.
Any cool high precision uses for them? Doesn’t have to be synth related
An high precision ohmmeter so you can measure them ? 
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Now that you mention it i could maybe measure themselves using a wheatstone bridge but i guess i would need at least 3 of them verified 
Quoting someone else’s Fediverse post:
I have just found, on Amazon, a USB peripheral which is a gearshift for a manual transmission car
Challenge: What is the funniest way you could utilize this peripheral in software
[Or in a synth – AO]
https://www.amazon.ca/Thrustmaster-Shifter-8-Gear-Compatible-Playstation/dp/B0C2JCX1TD
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This would be fun for chord progressions.
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Maybe you could use it to control… a drive module?
I’ll let myself out.
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I wonder how we could use these new programmable FETs? Fascinating stuff.
A new reconfigurable field-effect transistor and memory device based on a 2D heterostructure A new reconfigurable field-effect transistor and memory device based on a 2D heterostructure
I got a bunch of SN74HC595 of shift registers to expand the Arduino output pins, and as it typically happens, I have quite a few extras. Does anyone know of any clever/crude way where I can use a SN74HC595 in a waveshaping or modulation application?
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A cascade flip flop array to add stepped sweeps to a vca or filter? Random percussion trigger? A panning module? Control some digi-pots on a sequencer? Spin through a microphone array? A nice necklace perhaps?
I have more but the space is limited. Enjoy!
Edit: ooh and stacking the chips can generate some odd results
I should point out that most of my shift register experience is derived from making walking robotics. 
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You can make a digital noise generator, something like this:
The 74hc595 should work in place of the 4015’s
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@Farabide The cascade array and random trigger sound interesting, thanks! Do you happen to have any links to schematics?
@gasboss775 I just happened to get a few extra CD4093s today, so a good opportunity to breadboard this, thanks!
Keep them coming!
Is this a hardware version of some sort of LFSR (linear feedback shift register)?
Some time ago I build a binary counter using a CD4040 which I often use as a clock divider. This then may be a central part of the timing in a patch. When I was looking at an R2R network the other day (in my PC days I had one of those connected to the printer port and used that as an 8bit DAC!), I thought this could maybe be a nice addition to the binary divider, making a saw tooth which I might use as an LFO. So I drew up this schematic and added 2 opamps for good measure to be able to offset the saw tooth. However, I was thinking this “LFO” might be of very limited use as the frequency of the ramp is always linked to the clock and it will always be a realy low frequency anyway as I can not crank up the clock to a very high frequency as this will of course influence all other parts of a patch. But maybe anyone of your creative minds can come up with a use for an LFO like this that I have not thought of?
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Hi. I’ve nothing specific: the cascade array is created when you chain the 595s together for large led arrays with it’s own clock. Lots of options for corruption in modular synths. And oddly enough quite fiddly to get working in my experience.
A random trigger is and array as above but add in an lfo to speed up/speed through steps. Not exactly random, more playable.
Yes it is, yes indeed it is.
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If you want to get the full 10 bit resolution from this DAC, then the resistors in the R2R need to have at least 0.1% tolerance or better. Thats assuming you needed the 10 bit resolution. I suspect that for the most part you won’t…
As for what to do with it, basically you have a modulation source that will repeat either every 32, 64, 128 or 256 bars depending on which output is driving the sequencer.
Justif the top of my head you could modulate volume (vca) timbre(vcf or oter waveshaper, the decay time of an envelope, the delay time of a digital or analogue delay.
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I wrote one in software the other day as the ‘arduino’ library I was using in a project involving a BluePill was repeating the same numbers too often. Ha, the software version is easier to implement than the physical thing.
@Jos Regarding the DAC circuit in post #115, I couldn’t get it to work on the stimulator
I played around for awhile and came up with this (6 BIT) alternative:
The capacitors are to suppress spikes, probably unnecessary given the slow speeds that would be involved in the intended application.
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