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    • #7480

      Hi All,

      a couple of centuries ago I found an unknown PCB with 2 transistors, several resistors and an electrolyte capacitor. After drawing the schematic and doing some tests I found out a simple but interesting application, which I converted some months ago to Lectron:

      As everybody can see I built some blocks of my own to be near to the original. With the LDR – and the upper switch position – the light will be ON at night and will be automatically switched OFF in the morning (good for simulate “being at home” while traveling around the world…). This circuit may be a good experimental field with different resistor values, with a relay instead of the bulb or as a counter – with digital blocks or electro-mechanical  counters, like this one built by Mr. Gürth around 1970:

      Much success!




      • This topic was modified 3 weeks, 6 days ago by Guenni75.
      • This topic was modified 3 weeks, 5 days ago by mwpeters75.
      • This topic was modified 3 weeks, 5 days ago by mwpeters75.
    • #7484

      Hello Günther,

      This is a neat and functional device 😀

      I’d like to add this to the integrator circuit I proposed a while ago.

      So we will be able to count the events of lightness and darkness.

      Would you also like to design a circuit around this ?

      I will also do my best to come up with a proposal.


      • This reply was modified 3 weeks, 5 days ago by LectronFan.
      • This reply was modified 3 weeks, 5 days ago by mwpeters75.
    • #7486

      Hello Frank,

      I don’t have the time the next month to plan any block / extension with this circuit because a lot of other nice projects have to be introduced and others completed.

      Just this evening I finished my latest project AM Modulator / IF Adjustment Generator – it’s a low cost and possibly the smallest version ever! This is VERY useful for adjusting all AM Broadcast Superheterodyne amplifiers to best function and has nearly matchbox format (66 x 41 mm):

      There is also a subset as 1003 kHz/kc modulator (transmitter) as Lectron block (see Card File) and as a built-in unit of the Lectron Component Tester  (M.P.-version).



      • This reply was modified 3 weeks, 5 days ago by mwpeters75.
      • #7492

        Thank you for keeping the wonderful ideas and circuit designs flowing!  Just fantastic!!

        Günther, perhaps you could reach out to Mr. Gürth and invite him to join and participate in the forum.  I am sure that he would love the creativity that you and Frank have exemplified here and who knows, maybe he has a few ideas to share.

        Thanks so much to both of you!




    • #7493

      Hi Günther and Michael and everyone else !

      This is indeed a handy tool to adjust if and rf stages of an AM receiver.

      I always had difficulties to adjust !

      As for the night light circuit above, I opened the Lectron 1205 box and found a Silicon PNP transistor, ready to perform in your circuit !

      I even made a cool modification and used only the original Lectron blocks.

      The circuit is very sensitive to light, even the smallest light on the LDR will turn the lamp off.

      What is even more funny, at normal light the lamp will start to flicker ! At dark, the lamp stays on. You can always remove the 560 Ohm resistor to stop the blinking.

      But let’s combine this blinking circuit with the integrator. You can see the reading of the meter slowly increase with each blink.

      And if we only want to count the times the LDR was sufficiently lighted, just remove the 560 Ohm resistor.

      Here is a picture,


      LDR integrator

      • This reply was modified 3 weeks, 4 days ago by LectronFan.
      • This reply was modified 3 weeks, 3 days ago by mwpeters75.
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