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  1. WHONOES

    Where can i buy the mosfets i need for my project?

    Agree with (*steve*).
  2. WHONOES

    Where can i buy the mosfets i need for my project?

    Might I suggest using an IRF530 for the N device and its compliment an IRF9530 for the P device. Both can be obtained from Newark Element 14 for $1.39 and $0.95 respectively. They are both TO 220 parts and will probably need to be mounted on a small heat sink with suitable insulating pads and...
  3. WHONOES

    Help with single shot pulse using a waveform generator.

    I should imagine it could be done with a dual 555 which is a 556 with one providing the pulse period and the other doing the pulse width. And both can be made adjustable using potentiometers.
  4. WHONOES

    PSU advice

    That's fine.
  5. WHONOES

    Wiring Batteries?

    Buy batteries with leads attached. If using LiPo's there is a multitude of them on the model plane / car / boat market.
  6. WHONOES

    Leakage voltage in relay mecanical

    Indicate where you are measuring the voltage>
  7. WHONOES

    PSU advice

    I would add a panel mounted 20mm fuse holder adjacent to the IEC inlet. It is not good practice to rely on the mains cable having the correct fuse in it as it is possible to pick up any old lead and use that without knowing its provenance. Connect the Live of the connector to the tip of the fuse...
  8. WHONOES

    Current passing for regulator IC's

    Why not use a voltage regulator that is capable of delivering the current you require. They are freely available.
  9. WHONOES

    DIY voltage Regulator

    Small update on previously supplied circuit. The original works fine but the j fet is limited to about 35V. The newer circuit is good to about 50V though you will need to use the A version of the 2n2904. Other than that, everything else is the same. Also attached is a simulation graph showing...
  10. WHONOES

    Help with fence charger schematic

    1) You are not dissipating the energy into a spark gap. One end is connected to the voltage source whilst the other is connected to the fence thus discharging the circuit energy into the fence when the spark gap breaks over. 2) The size of the gap controls the voltage applied to the fence by...
  11. WHONOES

    DIY voltage Regulator

    See circuit attached. It is an oft' forgotten simple voltage regulator update with an FET. It gives much better load regulation than the BJT version.
  12. WHONOES

    Help with fence charger schematic

    See below schematic and graph for 15.7Kv generator. Note that you will require a spark gap between the output and you fence otherwise nothing will happen. You may create your own spark gap. The size of the gap will determine the strike voltage. Air ionises at 3Kv per mm so, if you want 12Kv set...
  13. WHONOES

    Op amp LM339 help

    If all you want to do is convert a 2.5V pulse of level into a 5V pulse or level. 2 transistors and a few resistors will do the job. See pictures attached.
  14. WHONOES

    PCB layout software?

    Try easyPC. It comes in various sizes and prices.
  15. WHONOES

    Beginning electronics, understanding whats actually happening

    Agreed, the Horowitz book is essentially the trade bible.
  16. WHONOES

    What should I get for beginning electronics?

    Absolutely. Been doing this for 50 years and learn something new every time I start a new project. Fascinating innit. Best way to learn is to start with the basics. Ohms law is fundamental. Learn how and why the various types of transistors function etc etc.
  17. WHONOES

    The LED is lightly glowing when switch off state. Please explain

    Correct. With Q1 not conducting current will pass through the base emitter junction of Q2. This is because in this state base emitter of Q2 is analogous to a forward biased diode.
  18. WHONOES

    DIY wire insulation/enamelling

    You can get double insulated wire (maybe even triple insulated) the insulation is wound on the wire rather than using and enamelling process. It is not cheap but can hold substantial voltages. Inter winding capacitance will be higher than enamelled. It is some years since I had cause to use it...
  19. WHONOES

    Help with fence charger schematic

    Haven't forgotten you. Have done a fair bit of simulation. Will post a circuit soon that will generate 12 to 14Kv.
  20. WHONOES

    PSpice Bipolar Junction Transistors Modeling

    Try a different spice package called SIMETRIX. It is a professional product costing many K£. You can download a free trial version that you can keep for ever. There are limits on circuit size for the free version but you can simulate surprisingly large and complicated circuits with it. I had a...
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