neil's webbly world

me@njohnson.co.uk
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Latest News

  • Goodbye old friend...

    Since acquiring the DDA D Series desk I have decided to break the older AHB desk into spares for other System 8 users. I am also taking the opportunity to dig deeper into the circuits to see what can really be achieved, with lots of bench testing. One idea is to put together a smaller 4-channel desk to use as a test bed for circuit ideas.

  • Another desk...

    I took the opportunity to acquire a classic DDA D Series desk in need of a full ground-up restoration.

  • Smooth Moves

    Following the recent move from the previous service provider over to Mythic Beasts I have also taken the opportunity to explore the generation of equations using MathJax. Only a couple of pages so far have been rejigged (here and here), but I think the results look much better and more consistent.

  • Math Is Fun!

    Or...What ABCD matrices are and why they are useful in circuit analysis.

    This page guides the reader through what at first looks like tricky maths, but with the help of readily available computer tools makes analysing complex passive circuits quite easy.

  • Ring Modulators

    Ring modulators have been around for a long time, first developed for telephone systems, and now used extensively in radio telecomms, and since the 1950s also in electronic music. I've written up some of the history of the ring modulator since my efforts at correcting the wikipedia page seem to upset the electronic music crowd.

  • Oscillator Linearity

    Linear oscillators are readily available. But how well do they work in musical applications? This page looks at linearity as a measure of how well they can play notes on an exponential musical scale.

  • Electronic Noise

    Noise in electronic circuits is usually not wanted. I put this page together while I was designing some low noise analogue circuits and needed a quick reference on resistor thermal noise and how it relates to op-amps.

  • Some Thoughts on Test Equipment

    Electronics engineers can get a bit particular about test equipment. I've added a page with some of my thoughts on the matter.


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