Wednesday 17 February 2016

Electronics - Discussion

Changed 31-07-2021, 01-08-2018

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

Crocuses open in the morning light. February 2016, IXUS 60 
Not all computing is electronic, clockwork or is 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 their 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.

Bicycle blog pages include Sturmey-Archer Dynohub maintenance and electrical aspects and another blog electronics project to manage the power taken under varying conditions.  Such as battery charging on the downhills, run the lights only when going uphill and restful intermediate on the flat.  This second bicycle blog could be developed into a high-value odometer/fuel gauge/battery charge styled bicycle instrument.
Sadly the quality of new bicycles has deteriorated since the 1970s and turned from bikes that are light to pedal comfortable and feel like they float, sports bikes that are amazing or child bikes that are heavier work but easy to ride.  To all regular bikes being heavier work.  The best ever bikes were made before 1961 to last 100 years, oiled and maintained fortnightly or every 100 miles at the height of bicycling in the UK.  Engineer's used to design products to last and work well just like doctors, nurses, artists the craftsmen they used to be.  Whereas the Campaign for Real Ale has empowered people to use their buying power to improve British beer.  The Far East and European car manufacturers now make long-lasting low maintenance cars whilst notoriously greedy, short-term, bad management and government frittered away the best engineering, textile and film industry the British once had.  A culture of not caring and cynicism has been cultivated.  But the system does not work for the little people who now do not have slack in their work and the systems they run fail rather than cope with overload they would have coped with 40 years ago.

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

Discussion on webpages Electronic and Engineering;


  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.


  3. The quality of this documentary is very high and the story told is very interesting, though known but nothing like with the feeling and detail told. Many of the comments made same the same thing and that it is a shame that documentary can not be told straight in this way now. I agree and thaT is part of why I got rid of my tv in 1988.

    Boys learnt radio as an art used to create a uniquily British people who could solve problems.