Search results

  1. A

    Micro FM TX (Micromitter)

    A good friend of mine in Australia bought one of these kits. He was having some problems getting it to work properly. He posted it to me to look at. Here are my findings and some modifications I did. I will address it point by point: 1) Move this cap closer to pin 12. The PLL Vcc is very...
  2. A

    Negative resistance experiment

    Here is a simple experiment to see the effect of negative restance from a reversed biased transistor. It will happen at a certain bias level. If you copy my circuit then the same values should work for you. We would expect the voltage to decrease when we add resistor R2 as we will be drawing...
  3. A

    Small FM Transmitter 1965!

    This transmitter dates back from a 1965 electronics magazine. Circuit looks very much the same as many circuits on the web today. Some things never change.
  4. A

    Function Generator + LCD (Design Idea)

    Nobody should be without a function generator. I know there are chips that you can use, but it is still good to learn how these things work. The stand alone chips have very limited output power and the lower spec parts may have quite high sine wave distortion. Here is a design I did using one...
  5. A

    Oxygen Sensor Tester (Design Idea)

    Recently a friend
  6. A

    Modifying a Belkin Tunecast for more transmit power

    http://www.jiggybyte.com/IndexAnon.php
  7. A

    Simple inductance tester

    From the latest EDN magazine "Cheap and easy inductance tester uses few components" full article here http://redigitaleditions.com/Repository/EDN/2007/04/12/EDN070412.pdf#OLV0_Page_0111
  8. A

    Duty Cycle control for square wave inverter

    It appears that a lot of members are interested in building simple square wave inverters from diagrams on this forum. Problems with these designs are that the drive wave to the push pull transistors or fets does not have any dead-time or duty-cycle control. Dead time makes sure one side is...
  9. A

    Modifying a squarewave inverter for sinewave

    I touched on this subject in another post. Here the basic information to do such a modification. The diagram shows the basic blocks of a squarewave inverter with the two resonating elements (C1, L1) added. The values are load dependant and the values shown works for a 100W load. In the first...
  10. A

    SPAM problem

    These spammers must be getting desperate if they now have to invade groups like this. I wonder how difficult it is for admin to just block their IP's from registering again. There must be a way to stop these idiots from spreading their filth here over and over again. They can easily register...
  11. A

    FM deviation meter

    I am building a FM stereo transmitter from a kit and need to measure my modulation or also called deviation when on air. Where can I find a circuit to do this? The only thing I found was here http://www.edmdesign.com/mic.htm where they use a small radio. Any idea what the "additional...
Top