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  1. bertus

    Heathkit AR-15

    Hello, Here is the extracted amplifier part of the posted schematic: It looks like a C-E short of Q201, as both are at 0 Volts. Could you take out Q201 and measure the transistor? Bertus
  2. bertus

    LED Edison-style patio lights

    Hello, Here is the amazon page about the lights: https://www.amazon.com/HueLiv-Changing-Dimmable-Resistant-Commercial/dp/B0861PT9D7/ref=sr_1_5?dchild=1&keywords=HueLiv+2-Pack+49FT+Colored+Outdoor+String+Lights&qid=1608056542&sr=8-5 Bertus
  3. bertus

    32kHz crystal

    Hello, How did you test the crystal? When it is a single crystal, you will need to make an oscillator with it. In the attached PDFs you will find some oscillator schematics and other info for crystals. Bertus
  4. bertus

    32kHz crystal

    Hello, When you say it is cracked, it must have been mechanicaly mistreated. Crystals are small pieces of quartz crystal or a synthetic quartz grown crystal. https://en.wikipedia.org/wiki/Crystal_oscillator They can not withstand bumping. bertus
  5. bertus

    Comedy Thread

    This 0.01 uH inductor.
  6. bertus

    Video monitor cable adaptation

    Hello, That will likely be not simple. The incoming signal must be synchronized with the original signal, if you want to "mix" it. Here are two pages with an explanation of the 15 pin video connector: http://www.hardwarebook.info/VGA_(15) http://www.hardwarebook.info/VGA_(VESA_DDC) Bertus
  7. bertus

    And now something weird

  8. bertus

    Has anyone here ever used a serial screen?

    Hello Ratstar, The 60 Hz you mention is the vertical frequency of a CRT television. The horizontal frequency is already much higher like 15600 Hz. The "pixel" frequency in a monitor can be in the MegaHertz range. All of this has nothing to do with the question of the TS. In the old days there...
  9. bertus

    COVID-19

    This is a hard one:
  10. bertus

    COVID-19

  11. bertus

    LC circuit Mutual Coupling

    Hello, Is the LC tank connected to ground or the 5V? Try to post a schematic. You could use paint and the following sheet to create it: Just copy from the sheet and paste it into your schematic and connect the parts with some lines. Bertus
  12. bertus

    Comedy Thread

    Tailand bridge collapse:
  13. bertus

    Help identify?

    Hello, I have cropped the picture: It is likely an inductor: https://www.newark.com/eaton-coiltronics/hcm0703-1r0-r/inductor-shielded-1uh-22a-smd/dp/77R1538 Bertus
  14. bertus

    Woo-Woo Infrasound and leaky feeders

    Hello, How do you expect the lower as 20 Hz signals being transported over ethernet? https://en.wikipedia.org/wiki/Infrasound Bertus
  15. bertus

    Comedy Thread

  16. bertus

    30A LED dimmer will not work for controlling electric throw?

    Hello, A quick look tells me that the 555 and 358 are powered by the 78L05. That way the mosfets will not be driven hard enough to work cool. Replace the 78L05 with an 78L10 and see if that changes the heat production...
  17. bertus

    30A LED dimmer will not work for controlling electric throw?

    Hello, Make some sharp pictures from the component side and the PCB traces side. The pictures must be shrinked to about 300 kB to be able to post them. Bertus
  18. bertus

    30A LED dimmer will not work for controlling electric throw?

    Hello, Can you trace the 78L05? Does the 78L05 feed the 555 and 358? What is driving the MOSFETs? Is it from the 358? Bertus
  19. bertus

    Paper Shredder ir paper detector

    Hello, You already have a thread for the shredder: Paper Shredder Fault Bertus
  20. bertus

    Help with circuit design of solar powered dog collar

    Hello, This page of the Battery University tells you more about the charging properties of the NiMH batteries: https://batteryuniversity.com/learn/article/charging_nickel_metal_hydride Bertus
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