Ted is a fan of soldering AND stock photography
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Ted is a lifelong electronics hobbyistHe studied engineering physics in college.Full color faxes were a thing in Japan but never took off elsewhere.After working on scanning equipment, he moved on to doing networking work.He also did some consulting after Cisco.Mid-way through his career, he went back to graduate school.Wrote a paper about finding telephone wires using LIDAR for helicopter pilots.Transitioned into AR, sort of like Projection Mapping. It was used for architectural daylighting simulation.Going back to school is tough for what you remember. Ted had to relearn linear algebra. He recommends using Gilbert Strang's lectures, which gave more context.After school, Ted did consulting with a few partners, mostly New England.Ted got started posting to Hackaday with 2016 HaD prize.His first entry was the "Diode clock", which utilizes the fact that diodes act like switches for RF when you pass DC current through them."Upping serendipity quotient"Using diodes as an AND gateUsing pin diodes for a doppler radio project1n4007 can act as a crude pin diode at certain frequencyBuilt digital clock that uses diodes for the countersAssembly instructions - 46 boards!Power supply is around 6 MHzOne of his other popular projects is the Tritiled, which helps figuring out where things are in the darkBased around the idea of tritium lightsModern LEDs are extremely efficient at a certain currentDroop happens at higher currentsThe 8 GHz sampling oscilloscope is a more recent projectResearch came out of the diode clockSchottky diodes for samplingTek S4 sampling head 14.5 GHzDiodes can switch in 10-15 pSStroboscopic effectEquivalent time samplingTek 11801 from 1989Nyquist still appliesVerifying on the bench is difficultPaper from picosecond pulse labJim Williams using an avalanche diode or a step response diodeLooking at RMS errorAnother architecture 1975 by SP McCabeUsing a fast comparator to sample waveform, similar to a successive approximation ADCADCMP582That's the time base calibrationWhat will people be able to build with an 8 GHz scope?Using it to measure transmission lines on PCB boardsUsing Time Domain ReflectometryTed has a splitter TDR headTracking generator + Spectrum analyzer = Scalar network analyzerRigol came out with cheap spectrum analyzer, DSA815, Ted got one of the early unitsTracking generator outputs signals that are the same as the frequency on the spectrum analyzerTed gave a talk about this at last year's Hackaday SuperconferenceThere is no phase in an SNASNAs are harder to calibratePaper was about how to do two measurements to compensate for errors in the generatorChris has a friend doing Python scripting on test equipment via their ethernet jacks.You can find Ted on Twitter, Hackaday.io and as a writer for Hackaday
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