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  1. (*steve*)

    Transformer of Unknown Rating

    In terms of power rating, it is pretty much field with weight. If you have a transformer rated at 100VA, then another with a similar weight will have a similar rating. If the are multiple windings you have to guess (possibly based on wire gauge) the split between them.
  2. (*steve*)

    Looking for advanced soldering tips

    Some of that advice is a bit dodgy. My recommendation is to take any conical tip you have and carefully throw it as far away as possible. Replace it with a double flat (screwdriver) but for general soldering. The site of the to allows you to use many possible surfaces from one corner of the...
  3. (*steve*)

    Components Buyers Guide [for Dummies]

    That diode should be fine unless you exceed the input current or want an output voltage that's to high. There's nothing in that circuit that will limit the input current.
  4. (*steve*)

    Transformer of Unknown Rating

    And you beat me to it. Glad you're still alive :-D
  5. (*steve*)

    Transformer of Unknown Rating

    If you know the blue wires went to 220VAC then you could connect them to 220VAC (via a 15W light bulb) and carefully measure the voltage on the other windings. In this case carefully means you connect the meter to the leads before you apply power and you touch nothing while the power is...
  6. (*steve*)

    Crafstman Lawn Tractor Reads 35VAC Across Battery

    You have a cheap multimeter. :-). Don't expect the AC range to give you anything sensible if there is any DC present. If the AC reading is 2.83 times the DC reading, then you're just reading the DC.
  7. (*steve*)

    Components Buyers Guide [for Dummies]

    Generally speaking the diode in this type of SMPS should be rated for the output current or higher (this should be the average current rating, not the peak). The voltage rating should be greater than the output voltage. However, since Schottky diodes have significant leakage near their rated...
  8. (*steve*)

    A Current Balance Circuit for LED Strings in Parallel with Polyswitch Protection

    I think you should start at the beginning with respect to the current limit calculations. Your calculations for base current are way off. Your calculation of the the resistor value to provide this current is wrong. Or at least the value you get is out by a factor of maybe 1000. Your method...
  9. (*steve*)

    Solid State.

    Or the strength of your Christmas tipple. :-)
  10. (*steve*)

    Confusion about oscilloscope setting

    At 5kHz, each cycle takes 200us. If you want 4 of them that's 800us, so 80us per division. If you can't choose this, either 50us or 100us might be the place to start. Edit: you need a slower timebase to see more cycles, so your error was to divide rather than multiply. Then I think you made...
  11. (*steve*)

    Woo Hoo HP5316A

    Here is the difference in clock rates in the 3216 before and after a very quick and rough adjustment.
  12. (*steve*)

    Transformer Help

    Green is a color I would not associate with mains wiring (except as an earth, which this wouldn't be). For 110 vs 220 volt windings you would likely have 2 separate windings placed in series or parallel to allow operation at the same power levels.
  13. (*steve*)

    Transformer Help

    For a step down transformer the mains input leads are typically thinner than the secondary output leads. However the black and white colours are suggestive of mains input. But the green tapping is not. All up, I would be very careful. Sorry for the non-answer. Whatever you do DO NOT just...
  14. (*steve*)

    Confusion about oscilloscope setting

    In a direct answer to you questions, no, and no. But the information answering the former question should be available and preferably easy to obtain on the screen of your scope. In answer to the second question, you should set the timebase in order to see a useful amount of signal. Your scope...
  15. (*steve*)

    Physical difference between low/high transformers?

    Colin, I think you may have omitted to read the very first reply. And the second.
  16. (*steve*)

    Physical difference between low/high transformers?

    Number of turns will also be very different. Bifilar windings (that my phone really wants to call "Butler soundings") are also more often used.
  17. (*steve*)

    Merry Christmas

    A happy Christmas, Saturnalia, Hanukkah, or whatever else you may be celebrating!
  18. (*steve*)

    Need to know suitable value of capcacitor for my PCB

    Yep. Any voltage greater than 51 volts will be fine. Usually we like a bit of margin, so 63V (a common voltage rating) is what was suggested. Higher voltage capacitors may be physically larger but as long as they fit they will do fine.
  19. (*steve*)

    why connect a jfet gate to source?

    You can use them as constant current sources. However there is quite a spread of Idgss between devices. There are commercially made 2 terminal devices commonly known as "constant current diodes" which are essentially jfets with the gate tied to the source. These devices are made in a series...
  20. (*steve*)

    Modifying MOT to get 40KV

    The main problem as I see it is that @Lash432 may not have any significant experience with EHT. And at these power levels, he may not last long enough to get it.
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