North Coast News

One minute op amp analysis
2018 Mar 11th

One minute op amp analysis

You can understand most op amp circuits with just three simple rules. If, through negative feedback, the op amp can bring its inputs to equal voltage, then it will do so. Otherwise, it will drive its output near whichever power supply voltage co…

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Voltage control modifications
2018 Feb 25th

Voltage control modifications

There's a recurring thread that comes up again and again in SDIY fora, where someone asks how to "mod" an existing device that is not voltage-controlled to give it a CV input. Sometimes this question is asked in relation to a specific product, in wh…

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Modular synthesis intro, part 5: Saving money
2018 Jan 21st

Modular synthesis intro, part 5: Saving money

This is Part 5 in a series that started with Part 1.Back in Part 3 of the "intro to modular" series I said it would cost about US$1000 to US$2000 to get started in modular synthesis, and I said that although there are ways to economize, they are real…

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Random thoughts on negative resistance
2018 Jan 14th

Random thoughts on negative resistance

It's been an exciting week here at North Coast. Since selling out the first batch of Leapfrog filters, I've been busy making more. That's still in progress. Then just yesterday I gave a talk at Frequency Freaks, here in Toronto, and that see…

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Ribbet!
2017 Nov 12th

Ribbet!

The Leapfrog VCF does not actually go "ribbet," at least not without some effort. But after being told by one friend I showed it to that most people don't want to make real music with their modulars but just want something that goes "uuuuuuuuu…

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Preferred values for resistors and capacitors
2017 Oct 29th

Preferred values for resistors and capacitors

You've probably noticed that although resistors and capacitors come in many different values, some of which seem like they could be randomly chosen, there's nonetheless some sort of logic to it. You'll see power-of-ten sizes like 1kΩ, 10kΩ, 100kΩ…

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Temperature compensation with NTC thermistors
2017 Oct 22nd

Temperature compensation with NTC thermistors

The panel contractor says they dispatched the first production batch of MSK 007 Leapfrog VCF panels to me on Friday, and those are the last remaining physical items needed before I can launch the module; so I'm still hopeful that I can ai…

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The Celebrated Leaping Frog
2017 Oct 15th

The Celebrated Leaping Frog

I've spent most of this week working on the second and third prototypes for the Leapfrog VCF. I'm hoping to have this product available for sale by the end of the month - maybe in time to have some kind of spooky Halloween tie-in for the launc…

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Circuit board shopping
2017 Sep 10th

Circuit board shopping

This week I'm planning to order the prototype boards for the Leapfrog Filter, and it makes a good opportunity to go through some common questions beginners ask about shopping for PCBs. When you go to buy PCB production services you're typically hit w…

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Video picks
2017 Sep 3rd

Video picks

I've been busy this week dusting off the design for the Leapfrog Filter. I really did most of the work on it back in 2016, and I even built a prototype which works pretty well, as you can hear in audio demos like this one. I'm hoping that will tran…

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