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  1. BobK

    if there possible for pic to faulty?

    Alright! Now you get to play with your program (the fun part, for me.) Bob
  2. BobK

    Design question on microcontroller and TIP122

    0, because they come out of my parts cabinet. Bob
  3. BobK

    Why didn't I get the voltage drop expected on diode rectifier?

    Actually, if you look at the data sheet, the drop is 1.1V at 1A. Bob
  4. BobK

    Voltage Divider/EL Wire Circuit Help

    Given that EL wire draws very little current, I think a potentiometer across the output of the inverter might be the better way to dim them. Bob
  5. BobK

    Old Component Equivalents

    Why? Why not build something using modern components? Bob
  6. BobK

    Design question on microcontroller and TIP122

    A TO92 transistor like the PN2222 can dissapate 1/2W. At 250mA and say 0.2V when saturated, it should be dissapating only 1/20th of a watt. No problem at all. Bob
  7. BobK

    Microwave Transformer Isolation

    That makes more sense. bob
  8. BobK

    Help Googling circuit names!

    Actually, he want 2, one rising edge and one falling edge triggered. Bob
  9. BobK

    Design question on microcontroller and TIP122

    At mouser.com: tip122 $.050 pn2222 $0.06 NTD4963N (mosfet 44A, 13.9mOhm) $0.19 (this is a great bargain) So, no, the tip122 is not the cheapest solution. And if you want to go surface mount, there is: NX3008NBK,215 (mofset, SMD, 400mA, 1.4Ohm) 0.05 Bob
  10. BobK

    Microwave Transformer Isolation

    Well, you can check it with an Ohmmeter. If there is continuity from the "primary" to the "secondary" is is not isolated. Bob
  11. BobK

    ATMEGA 328 ARDUINO External power?

    Presuming the Arduino has the chip in a socket, you can program it on the Arduino board, then move it to a proto-board or pcb. Bob
  12. BobK

    if there possible for pic to faulty?

    We'll stop laughing when you get it running! Did you try 22 or 27 pF capacitors yet? 15pF might also work for a crystal of that high frequency. Bob
  13. BobK

    Microwave Transformer Isolation

    If it is an autotransformer, as duke said, the secondary is not isolated from the line. An autotransformer has only one coil, which is tapped. The input is placed from one end to the tap and the output is from the two ends of the coil. Bob
  14. BobK

    UFO (undentified flat object)

    Very cool! That is a particularly nice takeout part. Bob
  15. BobK

    SMD/SMT Ideas, Kits, Experience...?

    I have not tried it, but I read an article about using an electric fry pan for reflow and, according to the author it worked better than any oven he had tried. I would like to try this one some time. Bob
  16. BobK

    Using a Laptop in the Mid-East - Convertor Question

    It might not if it doesn't mention it. The adapters I linked to are specifically for Israel, so it must be different than others. You want to look at your power brick, not the laptop to find out what voltage it can handle. Bob
  17. BobK

    Using a Laptop in the Mid-East - Convertor Question

    You don't say where you are coming from. I am going to assume U.S. If not, please ignore! Most laptop power adaptors will work on either 110 or 220V. Check yours and see if the is the case, it should say something like Input: 100-240V if it is. If it can work on 240V, then all you need...
  18. BobK

    OP amp scaling voltage

    I doubt it. That circuit is an inverting amplifier with an offset. If you are getting the right results, something is wrong. Bob
  19. BobK

    need help with simple 3v to 34v transistor relay/switch

    There is not pull-down. Bob
  20. BobK

    Please suggest a high to low level translator/ shifter.

    A voltage divider is all you need, assuming these really are signals with no significant power drawn. Bob
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