On the Strip board layout it calls for a .1nf Cap , but on the BOM it states 1nf , which one is it ?
Cheers
Daryll
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Where do you see 0.1 nF?
From https://www.lookmumnocomputer.com/projects#/cem-3340-diy-simple :
If it says 0.1 nF somewhere else that must be an error.
That capacitor determines the frequency range:
Presumably 0.1 nF would drop raise the range to ~0.5 Hz to 1 kHz ~50 Hz to 100 kHz.
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Smaller cap = higher frequency, no ?
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Oh duh. Is a complete sentence. …
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.1nF is not a thing. That would be marked as 100pF for sure.
Typo?
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That’s already been pointed out.
it’s the pin of the cap, not a decimal point, you can guess the second one on the ‘f’ of ‘nf’, that’s why that ‘f’ look strange.
But it’s confusing for sure !
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Looks like that dot was edited out in the basic version at https://www.lookmumnocomputer.com/projects#/cem-3340-diy-simple .
but in the images below it’s there. Yeah, confusing. But the BOM is right.
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welcome daryll, to our lmnc synth group hug of interesting tidbits and suggestions
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So I was working on making a AS3340 VCO on protoboard but a problem came 
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On the electric druid schematic we have a 360k pull up resistor,
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But on the Sam’s version there isn’t any. So is that normal? Or not needed? (I think it’s for tuning maybe?)
Thanks for reading and helpinn ^^
It’s not a pull-up resistor, but another “control voltage”, one that’s constant. As such it offsets the oscillator pitch by a constant amount. In the 1222 oscillator (which I think that schematic is referring to, not the “simple VCO”) there are an octave switch and a center note pot which perform a similar function but can be varied. The simple VCO stripboard has a coarse tune pot which serves similarly.
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Ooh okay now I see thank you a lot. So I can just replace it with a pot so I can change the coarse?
Yeah sorry I just wanted to use a similar topic so I chosen this one ^^
Or maybe it is a wee fly taking a rest?
I don’t have a 10k trimpot… can I use a 100k instead? Will it break, or just make tuning more difficult?
It’s connected as a variable resistor (i.e. wiper is connected to one end) so it’ll work, but the target resistance for 24k + trimmer is ~30k so you’ll end up tuning at around 6% rotation.
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Thank you for the quick reply… that sounds a little too precise. Guess I’ll wait, thanks.
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