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  1. (*steve*)

    ridiculous harvest

    I am in a place that pineapples "can't" be grown. Two years of growth here is probably equivalent of a couple of months growth in a more ideal climate. The fruit itself was probably growing for 6 months.
  2. (*steve*)

    Flyback transformer testing and replacement

    If certainly be looking for a replacement for that. How is Q9?
  3. (*steve*)

    50w rms into 8 ohm load amplifier circuit using single dc power supply

    The last couple of days I've been designing a circuit where I needed to work to ensure I'm staying inside the SOA for some components. Given that there is a significant possible range of values such as Vgs(th) I needed to do just that to ensure the circuit will not only continue to work, but...
  4. (*steve*)

    ridiculous harvest

    2 years or so after planting this, I get a single fruit before the plant dies. Is it really worth the effort? They do taste a lot better than store-bought ones though. Also, it's not green!
  5. (*steve*)

    Trying to make a LDR circuit work ?

    There are a number of problems with that circuit. The first is that the LDR needs to have a very low resistance for the LED to switch off. In your case, I'd estimate that it would need to drop below 3.5k (assuming a 9V battery). The second problem is that the LED would slowly go out as the...
  6. (*steve*)

    Flyback transformer testing and replacement

    OK, it might be a good time to check that none of the semiconductors on the primary side have failed short circuit (that's the most likely failure mode). Open circuit isn't good either :-)
  7. (*steve*)

    Flyback transformer testing and replacement

    That seems fine, but it's a very odd diode to use in that application. Have you checked the continuity between pins 7 and 9 of the transformer? If it's OK, put the transformer back in circuit and see if there's an AC voltage on the primary windings when the device is powered up. My guess is...
  8. (*steve*)

    Flyback transformer testing and replacement

    And between 7 and 9? Transformers are quite rugged components. They are not the thing I would first suspect unless there was physical damage or an awful smell coming from them. Was there an AC voltage across any of the windings? Is D6 shorted?
  9. (*steve*)

    Flyback transformer testing and replacement

    Transformers require AC. Connecting them to a DC source won't tell you much. It actually looks like a transformer (I thought it may have been a DC to DC converter). It is possible it might have an integrated rectifier, but I don't see any evidence of that. Did you pull it out of a circuit...
  10. (*steve*)

    Cheap N-type MOSFET for PWM driving many LEDs with 3.3 V logic?

    Here is the start of a resource that may help you. At the moment I've just linked to various related answers I've given, but the general principle is stated in the more detailed ones. Soon I will continue this with generic advice. I hope that helps.
  11. (*steve*)

    Direct connecting solar panel to 18650 lithium cell...

    How far would the cell discharge if the zener was left connected? (I suspect they would discharge to 3.6V or so)
  12. (*steve*)

    Selecting a suitable component

    (*steve*) submitted a new resource: Selecting a suitable component - Finding a component that suits your needs at the right price Read more about this resource...
  13. (*steve*)

    Selecting a suitable component

    0 - Contents A common question How Common? What's here? Finding that MOSFET General principles 1 - A common question One of the common queries we get is: How do I find a cheap <component type> for <use case> with <specifications>. This may be stated like "I need the best MOSFET to switch a...
  14. (*steve*)

    Direct connecting solar panel to 18650 lithium cell...

    Two 2.1V zeners would be far worse. Low voltage zeners have very soft knees. Using these would lead to your batteries being discharged. A single 4.2V zener would be better, but I would study both the characteristics of the knee and the tolerance of the zeners. If the tolerance is 5%, a...
  15. (*steve*)

    New layout sucks

    I'm magically back in the old format. And the option to change formats is back. Thanks... whoever...
  16. (*steve*)

    Change in site ownership

    @eerob, the ability to change themes has gone, and I am now stuck with the less functional "new" theme.
  17. (*steve*)

    Direct connecting solar panel to 18650 lithium cell...

    I recommend you place a shunt regulator across the lithium cell. Here is an example of a circuit that was modified for that purpose (set it to 4.2V and your battery will be safe). Diodes have a lower voltage drop at low currents, so the battery will continue to charge (at a very low rate) even...
  18. (*steve*)

    hi fellow hobbyists.. ?about sensors

    Vcc is your +ve supply, Gnd is -ve, and the out is the output
  19. (*steve*)

    New layout sucks

    And now that I need to do a search, I find I'm in the new format and I have no access to the advanced search or the ability to change back to the old format :-(
  20. (*steve*)

    what do I have here?

    I got these to play with them after I saw a report on the Q of a heap of crystals. Of the huge set of crystals tested, the ones in glass bottles had the highest Q (by a large margin). And these are really large crystals! I'd like to make a low frequency ovenised oscillator just for the fun of...
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