Wednesday, 17 February 2016

Electronics - Discussion

19-03-2015 Changed 01-08-2020, 29-07-2018

This page is also for readers to post comments or join in with discussion on the Electronics on my website.

Crocuses open in the morning light. February 2016, IXUS 60 
Not all computing is electronic, clockwork or be animal powered. Solar power may have servo systems to track the sun but these crocuses do that and other complicated processing. They protect their stamen by closing the flower under certain conditions. Other intelligent things such as choosing there environment and they may change the environment to suit them better part of Gaia system observed and spoken of by humans for millennia.

Croucuses closed on a shady day
Crocuses close in the overcast afternoon. Next morning they will open
again and there will be another flower  coming up on the left hand plant.

Blog - Electronics example of my work

Blog Electronics - Theoretical design example;
Playing and exploring things I do not have time to do at work. Also to a depth I would not do for work but is necessary in order to learn and use the things learnt.

Discussion on webpages Electronic and Engineering

More flowers have grown and the picture sparkles with the rain this morning.


  1. I am trying to simulate in LTSpice your Photo synchronous chopper amplifier demodulator (AL-0003-02B) on page
    When comparing your synchronous filter ADG1213 with the AD datasheet switch 1&4 are non-inverting and switch 2&3 are inverting logic. In your circuit the symbols are correct but the labeling and pinout IC1B and IC1D seem switched.
    Nevertheless when correcting this in my LTSpice simulation I still do not have alternating output over the capacitor C1 which I would expect giving the same clock to all 4 switches?

    1. Dear Klaus,

      Your evaluation of my circuit is an invaluable review for me thanks.

      You are correct to say that the analogue switch sub-parts or wrong and I find that in using these parts elsewhere that I had corrected them but I had not got as far as correcting my web-page. Since creating that project I have been in paid work and have used some of these designs as training exercises and I have been busy. I will update the web-page shortly.

      I will look at the text - I would not be surprised if I have not described properly what the circuit should do. With ambient light falling on the photo diode the average voltage at the output should be zero. But with light, say from an LED driven from the synchronous clock should cause a voltage output proportional to the polarity and current drive to the LED.

      I am sure you understood that anyway Klaus but C1 should have very little AC signal voltage with a simply modulated light source. With high ambient light the the voltage on C1 will have a small triangle wave ripple.

  2. March - April 2018 - Extensive changes.