Good attenuator in 8753D external test set Mike Fikes 2021-08-08 | This is showing S11 reflecting all of the power back in (open port 1). You can see a nice flat response at all attenuation levels. Compare with youtu.be/bXJYwIjCP2c which shows things prior to replacing the 85046-60006 attenuator in the 85046A external test set.
Smith Chart Calculations with Impedance Converter App [W2AEW] Mike Fikes 2024-02-05 | Run's through Alan Wolke W2AEW's videos on Smith charts youtu.be/gw1TYWwfvGk?si=fkEmS_oXeI-I5iNZyoutu.be/ImNRca5ecF0?si=Q6Rw7vBU9ROjMRVQcalculating the results using the Impedance Converter App, which is available on the App Store apps.apple.com/us/app/impedance-converter/id6474902691 and Open Source on GitHub github.com/mfikes/impedance-converter
Measuring line noise introduced by the Kunkin KP182 and BK Precision 8500 DC electronic loads Mike Fikes 2023-12-10 | Compares the line noise introduced by the Kunkin KP182 and BK Precision 8500 DC electronic loads, making use of a Tekbox TBCP1 current probe.
Using an MFJ-407B keyer to drive Morse Chat mobile app with paddles Mike Fikes 2023-05-14 | Source code: github.com/mfikes/morse-key-ble-bridgeThe keyer is connected to a button on the nRF board on the left, which is acting as an HID keyboard, connected to the phone. The Morse Chat app is set to straight key mode while the keyer is taking care of the iambic paddle logic.Much like the demo shown in youtu.be/_yfMRzepxrU, keyboard latency and jitter affects the ability to key the app effectively at high speed, but this can be mitigated by configuring the BLE parameters.
Morse code CW straight key connected to phone via BLE Mike Fikes 2023-01-04 | The app is Morse Mania. The device is an Android phone; I haven't sorted the same for iPhone.I suspect it is too slow to use this way unless further optimized in some way.A subsequent demo with paddles youtu.be/O0wdYhWQfyg
Morse code via an AWG (generated using ClojureScript) Mike Fikes 2022-12-24 | Generating morse code by modulating a 700 Hz tone with an ARB representing the code.The ARB was created in a ClojureScript REPL (relevant bits below), then spit to a file to load in the 33500B.(def dit [1 0])(def dah [1 1 1 0])(def space [0 0])(def W (concat dit dah dah))(def TWO (concat dit dit dah dah dah))(def A (concat dit dah))(def E dit)(def W2AEW (concat W space TWO space A space E space W))
HP 85 GPIB to generate random runt pulses Mike Fikes 2022-11-27 | Demonstration using an HP 85 to drive an Agilent / Keysight 33500B series signal generator to create random runt pulses, which are triggered on a Tek TDS 5104
Square wave sweep artifacts in Rigol DG1022Z vs. smooth Agilent / Keysight 33500B sweep Mike Fikes 2022-11-08 | ...
Comparing rising edge of Rigol DG1022Z with Agilent / Keysight 33500B Mike Fikes 2022-11-08 | A quick comparison of square wave rising edge shape for a Rigol DG1022Z and an Agilent / Keysight 3055B signal generator, when both are sweeping the square wave.
Bad attenuator in 8753D external test set Mike Fikes 2021-08-08 | This is showing S11 reflecting all of the power back in (open port 1). You can see (unstable) rolloff at low frequencies and a ripple with frequency, but only at certain attenuation levels. Compare with youtu.be/2-FFDrGkjZc which shows things after replacing the 85046-60006 attenuator in the 85046A external test set.
Harmonic distortion of audio frequency from Rigol DG1022Z Mike Fikes 2021-06-16 | Inspired by the measurements shown by Ruel Tmeizeh at youtu.be/t5CMkFVq8x4
Can you use an attenuator as a terminator / load? Mike Fikes 2021-06-15 | Checking to see if an attenuator can effectively be used as a terminator / 50 Ω load by looking at things in a TDR. IMSAI Guy's original video on the subject: youtu.be/WakbPENJHXA
Do RF connector adapters affect impedance? Mike Fikes 2021-06-12 | IMSAI Guy's original video youtube.com/watch?v=GOCD5DvOj5c
High Freq Content with SA LO Out Mike Fikes 2021-05-22 | Response to a nice video by IMSAI Guy measuring a high frequency isolator youtu.be/-rkqXxGU88s
Heterodyne Converter Microwave Frequency Counter Demo Mike Fikes 2020-12-09 | A demonstration of an HP 5347A microwave frequency counter, employing heterodyne downconversion of the signal, illustrating the comb generated by the frequency counter.See TSP #35: youtu.be/-RpwE_uxgjM
Esprit ClojureScript REPL in Cursive Mike Fikes 2020-06-25 | How to use the Esprit ClojureScript REPL from Cursive IDE
Esprit Charge Disable Thermistor Mike Fikes 2020-06-13 | Demonstration of charging being disabled if the board were to become warm.
Wave Folding Circuit (Buchla 259 Wavefolder) Mike Fikes 2019-10-27 | Demo of circuit from "Virtual Analog Buchla 259 Wavefolder" by Esequda, Pöntynen, Välimäki and Parker.
ClojureScript compiler tests in cljs-test-display Mike Fikes 2018-06-25 | Running the ClojureScript compiler tests using cljs.main and Bruce Hauman's new tool, cljs-test-display.
SHENZHEN I/O problem 1 in hardware Mike Fikes 2018-01-07 | A solution to problem 1 in SHENZHEN I/O (http://www.zachtronics.com/shenzhen-io) using logic chips. Here is how it works:On the left is a 555 timer chip which is used to generate the CLK signal. To produce the active (ACTV) signal (which is a square wave with a period of 12 clock cycles), the CLK signal is first inverted (via a 74HCT04, with is the 4th chip from the left), and then fed into a 74LS90 (the 2nd chip from the left). The 74LS90 is set up to divide-by-6 (see p. 231 of _TTL Cookbook_) with the output coming out of pin 6. This output is low for 4 cycles and high for 2 cycles. To convert this to the desired square wave, it is fed into a JK flip-flop (a 74LS76, 3rd chip from left) set up to toggle with every negative edge, thus producing the ACTV square wave which is displayed via the red LED, and the 2nd trace on the oscilloscope.The problem solution is the network (NETW) signal, displayed by the bottom trace on the oscilloscope. It needs to be low for 4 cycles, high for 2, followed by low and high for 1 cycle each. To produce it, first a binary counter is used (a 74HCT161, the farthest chip on the right). If you let the three lowest-order bits of this counter be t0 through t2, the solution is given by t2 ∧ (¬t1 ∨ t0). To express this using only ANDs and NOTs, it is re-expressed as t2 ∧ ¬(t1 ∧ ¬t0). This is calculated by using a QUAD-input AND chip (74HCT08, 2nd from right), and the existing HEX inverter to the left of it, with the result being displayed with the blue led.
ClojureScript Go Mike Fikes 2017-01-15 | My son wanted to make ClojureScript play Go. We wrote a small program using Planck to generate random moves using rand-int and some structure to prevent repeats. This is the result of playing out the actual game. He surprised me by pointing out that we needn't worry about the rule of Ko. :)
ClojureScript and optimized C Mike Fikes 2016-11-28 | Showing a calculation where ClojureScript runs at the same speed as optimized C.Source: gist.github.com/mfikes/c531a4801a84e2c06af11588ce29068e
Planck REPL Interruptibility Mike Fikes 2016-10-30 | A demo of using the FIPP printing model to interrupt printing of large forms in Planck.
Instant Clojure REPL Startup Mike Fikes 2016-06-19 | Demo making Clojure REPL appear to start instantly. Try it for yourself: gist.github.com/mfikes/844a9e6659a30eaf44dcb9170ebc739d
Testing with bootstrap ClojureScript Mike Fikes 2016-04-21 | Demo using a new ClojureScript compiler capability that makes it possible to use cljs.test in bootstrap ClojureScript.
Using Planck from Cursive Mike Fikes 2016-02-29 | A demo showing how to set up Cursive to use Planck.
ClojureScript REPL improvement Mike Fikes 2016-02-22 | A demo of a patch to the ClojureScript REPLhttp://dev.clojure.org/jira/browse/CLJS-1572
Planck indentation with Parinfer Mike Fikes 2016-02-05 | Using Parinfer to indent Planck http://blog.fikesfarm.com/posts/2016-02-10-indenting-with-parinfer.html
ChakraCore ClojureScript REPL Mike Fikes 2016-01-29 | Demo of ClojureScript REPL running on the ChackraCore version of Node, making use of Elbow (a small Node-based bootstrapped ClojureScript REPL using Replumb)
