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  1. (*steve*)

    Suspected static discharge

    It could be static, but it is far more likely to be pickup of interference on your long antenna. I guess that your long run of wire isn't shielded cable. Replacing the cable with coax would probably help, but you might get away with a capacitor at one or both ends. These will reduce the speed...
  2. (*steve*)

    Help with a Japanese Electrolytic Capacitor? prob an easy question!

    A photo would help. It might be tantalum, one of the newer polymer electrolytics, or something else.
  3. (*steve*)

    12VDC Backup supply

    Yes, and as per my first reply, a diode connected to both the 12V and the 9V battery should be used to isolate them from each other.
  4. (*steve*)

    NPN transistor still working? Strange ..

    Those of us who are old enough... Transistors operating in various breakdown conditions were a fad. Some significant early research (in the late 1950's) looked at it because it offered some interesting benefits. This is one interesting example. One feature which makes operating in this mode...
  5. (*steve*)

    Arduino based frequency counter design

    This is just advertising for a crowd funded campaign. I'm closing the thread.
  6. (*steve*)

    Arduino based frequency counter design

    Your use of abbreviations to designate ranges needs some serious thought. These abbreviations mean things already, using them for something else makes you look... well, it's not wise.
  7. (*steve*)

    Tubular Capacitor Polarity

    There orientation can certainly have an effect in a high impedance circuit where there is electrical noise. However this problem was far more prevalent when point to point wiring was used in close proximity to AC (used for heaters of tubes).
  8. (*steve*)

    NPN transistor still working? Strange ..

    Well... At one level, you're probably more interested in the flow or electrons rather than "conventional current". At another level, maybe you should get at least a little familiar with the basics of Kirchhoff's laws. Those, along with the understanding that current doesn't flow in both...
  9. (*steve*)

    NPN transistor still working? Strange ..

    A more interesting question is why the circuit operates differently from how it would if the transistor was replaced with a zener diode.
  10. (*steve*)

    Loud mains hum with Jaycar short circuits Vol 3 #12

    Having said that, if the preamp is clipping, then the gain must be reduced. For low noise, it's better not to attenuate a small signal before amplifying it (and thus the volume control normally follows the preamp).
  11. (*steve*)

    Loud mains hum with Jaycar short circuits Vol 3 #12

    I would recommend that you simply reduce the value of the 200k feedback resistor(s). We're still operating without schematics...
  12. (*steve*)

    ESP8266-01 with Arduino Nano issues

    The existing 3.3V regulator may be good for about 50mA, about half of what you want. A voltage divider is somewhere between useless and extremely wasteful. Get an external 3.3V regulator and use that.
  13. (*steve*)

    ESP8266-01 with Arduino Nano issues

    You've recognised that the 3.3V output can not supply sufficient current. What have you done to supply enough current to the ESP8366? Have you wired up an external 3.3V regulator? If you're powering it from 9V it may get reasonably warm unless heatsinked or in a fairly large package.
  14. (*steve*)

    Positive Tolerance of PV modules

    Typically a good solar panel will have a guaranteed output. To ensure this, the output power will typically be higher. For example, a 300W panel may be nominally 330W, with a range of outputs between 300 and 360W. So rather than calling it 330+/- 10%, they will guarantee 300W and specify that...
  15. (*steve*)

    NPN transistor still working? Strange ..

    We've looked at this before. This circuit will probably cause the LED to emit short flashes. The 1k resistor charges up the capacitor. At some point the voltage across the capacitor exceeds the sum of the forward voltage of the LED, the base-emitter breakdown voltage of the transistor, and...
  16. (*steve*)

    Equivalent Capacitor for 220r16 c4 (2)

    There are arguments to be made that it could be 22uF or 220uF. If you go to a supplier like digikey you can search for 22uF 16V tantalum surface mount capacitors and 220uF 16V tantalum surface mount capacitors. Have a look at the package dimensions. Does this match one better than the other...
  17. (*steve*)

    Loud mains hum with Jaycar short circuits Vol 3 #12

    Kling wrap? As in the clear plastic wrap? Aluminium foil would work better as long as you don't short anything out.
  18. (*steve*)

    Component Identification

    It looks like it's gotten very hot, but maybe not so hot as to make it go open circuit. If it is open circuit you may be able to expose a part of the wire near the middle of the resistor and measure the resistance to one end (and double it).
  19. (*steve*)

    Problem with robot made using arduino

    Sure, but what is all this stuff about lifting. Are those videos of your robot or someone else's?
  20. (*steve*)

    Loud mains hum with Jaycar short circuits Vol 3 #12

    Ok, that's fine. It eliminates several possible issues. I would recommend you place the preamp in a shielded enclosure and be sure that shielded cables are used to connect the inputs and outputs.
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