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  1. (*steve*)

    maximize efficiency of a solar panel charging a Li-Ion battery

    That seems unlikely. Is it just a battery, or is it a battery management system and battery combined?
  2. (*steve*)

    maximize efficiency of a solar panel charging a Li-Ion battery

    It might, if the sun were a 100W bulb 10 to15 cm from the panel. The output of a solar panel changes during the day. Depending where you are and how you place the panel, you'll only get the equivalent of 4 to 8 hours of full sunshine every 24 hours
  3. (*steve*)

    Capacitor tester in circuit

    FFS! Look at this post (the second image). It has everything to do with your 9V power supply. How can you call it a (say) 1000μF range when the absolute highest it can read is 900μF?
  4. (*steve*)

    Is it possible to use barometer module using UARTS?

    Not simply (to the best of my knowledge). They're two totally different interfaces.
  5. (*steve*)

    Capacitor tester in circuit

    I was referring to your capacitance meter. But on a desktop monitor I now see that the range is 2000uF x10 (on which the 4700uF capacitor measures 425uF) But your circuit is powered from a 9V rail!!!!
  6. (*steve*)

    Is it possible to use barometer module using UARTS?

    If you are going to use the UART interface then you will need to find a barometer with a serial (e.g. RS232) interface.
  7. (*steve*)

    maximize efficiency of a solar panel charging a Li-Ion battery

    If it is just the output of a solar panel, you should get maybe 70-80% of the short circuit current at 80-90% of the open circuit voltage. If the open circuit voltage is 5V and the battery is 4.2V it's a pretty good match already. If there's already some sort of circuit inside, then all bets...
  8. (*steve*)

    maximize efficiency of a solar panel charging a Li-Ion battery

    I would first connect a diode between the solar panel output and the battery pack and measure the charge current. any sort of switch-mode converter (that's not MMPT controlled) can get itself into a corner state where it loads the solar panel to a very low voltage and passes only a small...
  9. (*steve*)

    Products for PCB connecting

    See if you can insert two rows of 10 x 1 pin headers in there. Then get some mating sockets and connect your wires to them.
  10. (*steve*)

    Replacement for .5 MFD / 300 VDC Capacitor

    That new resistor (not a capacitor) must be mounted on a heatsink. Yeah, it will likely smoke if you don't mount it on a heatsink. I would probably get a 50W to 100W aluminium clad resisitor. It may be sufficient in this application without being attached to a heatsink.
  11. (*steve*)

    Capacitor tester in circuit

    So that's yet another option. Is that how it is wired? Why not use a single diode in each direction? Can you update the schematic to show the correct wiring?
  12. (*steve*)

    Capacitor tester in circuit

    Well, that's invalid too! Your capacitance meter is on the 2000μF range, so either that's a faulty capacitor or your meter does strange things when over range. If it is a 4700uF capacitor then it's measuring 4200μF. So is it 4700μF, 425μF, or 4200μF? You need (at least) your capacitance...
  13. (*steve*)

    Theory/reality mismatch in a transistor circuit

    Is it still 12V under load? or is it falling to around 10.5V? Assuming it remains close to 12V, the readings you're getting across the DC supply (13.9V) are indicative of the DC voltage varying from around 12.5V to 16V due to the ripple. My back of the envelope calculations suggest it...
  14. (*steve*)

    How Is This RC Circuit Dropping Voltage

    This sort of power supply is not isolated from the mains. It can result in a deadly shock! Therefore, we typically steer people away from using them.
  15. (*steve*)

    Capacitor tester in circuit

    However that's a pointless test as I pointed out before. The meter will never exceed 9V because your power supply is only 9V between ground at the +ve rail. Try doing that with a 4700μF capacitor. I would not trust any output of that circuit over 8V. It would be far better if the power...
  16. (*steve*)

    calculate high power led resistor

    It's possiblly a 1W LED, although if it's Chinese, I wouldn't put it past then to have used a 1/2W LED. Making some bold assumptions, it's drawing about 120mA and the LED is dissipating a little over 0.5W
  17. (*steve*)

    Capacitor tester in circuit

    Hang on. That's 2 parallel 560μF caps and it reads 1200μF
  18. (*steve*)

    Capacitor tester in circuit

    I was referring to this: Should we assume the same orientation as this: And if so, do you mean this? Which is nothing more than a pair of diodes in inverse parallel across the terminals. Why specify 4 diodes?
  19. (*steve*)

    Capacitor tester in circuit

    I note that the output of this circuit appears between the output of an op-amp and ground. Even assuming the op-amp can swing to the supply rail, the maximum output you'll get can't exceed 9V. On that basis, the result you get here: Is full scale, and doesn't really tell us anything (the...
  20. (*steve*)

    Theory/reality mismatch in a transistor circuit

    I don't see that you have measured the DC voltage to the circuit. And did you actually measure this or infer it?
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