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  1. (*steve*)

    LM317 2N3055 Variable Circuit Problems

    The measurement across the resistor is a measurement across the fixed (220R) resistor, or across the variable resistor?
  2. (*steve*)

    16 BIT RIGHT SHIFTER

    So, how far have you managed to get on your own?
  3. (*steve*)

    LM317 2N3055 Variable Circuit Problems

    The reason those meters read differently is that one has a real diode test position (and reads the voltage drop) whereas the other indicates the appropriate resistance range to test diodes (and reads a "resistance"). Use the meter with the real diode test position.
  4. (*steve*)

    LM317 2N3055 Variable Circuit Problems

    I just wanted to show you it works :) Even though I wound down the current limit, the circuit didn't try to exceed it, so I could have turned the current limit off without any change in behavior. Place some of your output capacitors at the input of the 317 and don't have any output capacitor...
  5. (*steve*)

    How is IOT different from Embedded Systems?

    For me, IOT simply means that the thing is a non-traditional device connected to the internet. "non-traditional" often means it's a microcontroller based thing rather than a general purpose computer (and I include phones in the general purpose computer category).
  6. (*steve*)

    LM317 2N3055 Variable Circuit Problems

    I'm using a 220 ohm resistor and that pot is almost certainly a lower power unit than yours. The current flowing through that is 5mA and the max power is 25mW (so I'm not afraid of smoke :-) I can wind the output voltage down to 1.3V -- no smoke. My input voltage is 12V, but let's wind that...
  7. (*steve*)

    LM317 2N3055 Variable Circuit Problems

    This circuit should look familiar:
  8. (*steve*)

    Need help designing a resistor sequencer.

    Most people make their own vactrols by sticking together a CdS cell and a LED. A couple of layers of shrinkwrap does wonders :-) Some people go to the additional effort of 3D printing little enclosures for them.
  9. (*steve*)

    Burned a solenoid with a relay timer, and I don't know why

    Yeah, the power supply sounds like it would be suitable. I doubt it is the problem. Chinese manufacture on the other hand... The problem may be the relay, not the solenoid. It is possible that the contacts have been damaged. Try putting a 0.1 uF capacitor across the contacts. Hmmmm...
  10. (*steve*)

    Battery charger

    I would recommend you get a proper charger. The batteries will last much longer
  11. (*steve*)

    Burned a solenoid with a relay timer, and I don't know why

    To make the user interface "correct" use NO rather than NC connections on the relay. This will also ensure that if your timer fails it is more likely to fail with the relay off and thus the solenoid off. The second thing we need is specs for the solenoid. Is there liquid/gas flowing? It is...
  12. (*steve*)

    Need help designing a resistor sequencer.

    There may be multiple causes for the noise. The first is that digital noise from your circuit is bring picked up inside the pedal. The second is that changing this resistor is changing some voltage level in the circuit (which is most likely because it's in a feedback loop from memory) and this...
  13. (*steve*)

    Insights On Powering Patch Antenna In Cell Phones

    It's done in software, and most likely a circuit module or function on a chip is turned off (our powered down). One of the simpler practical examples I've read is in the microcontroller section of The Art of Electronics in the section describing how to get a particular circuit to operate from...
  14. (*steve*)

    LM317 2N3055 Variable Circuit Problems

    That is probably a bridge rectifier. It's still quite possible the problems are external to your circuit. Frankly it may be time to think about using a 9V battery or something equally benign as a power source to begin with. I may try breadboarding the circuit myself and send you my pictures...
  15. (*steve*)

    LM317 2N3055 Variable Circuit Problems

    Do you have a diode (or 4 arranged as a bridge rectifier) between the transformer and the caps?
  16. (*steve*)

    LM317 2N3055 Variable Circuit Problems

    The only reason I can think o for the 317s to die, causing smoke like that is: 1) AC or unfiltered DC input 2) output capacitor causing breakdown of the pass transistor's BE junction. 3) some subsequent failure causing the input to short to the ref pin. I'm not certain this is a possible...
  17. (*steve*)

    Adding PWM speed control to Linear Actuators for TV control

    To detect stalling, you could use something like this: power input is on the left, the right goes to the PWM transistor and the H bridge. R1 has the value 1/s Ω where s is the stall current of the motor in amps. R2 should be about 1k, and R3, 10k. While the current through R1 is...
  18. (*steve*)

    Adding PWM speed control to Linear Actuators for TV control

    Here is one way to wire the limit switches: if the left is positive an the right is negative, then the limit switch S2 should open at the end of travel. This circuit allows the motor to be driven no further than the limit in either direction, but allows it to be driven out of it in the...
  19. (*steve*)

    ESP8266 AT Command

    The previous string had a space as the password. Maybe you left it in when you tried it last time?
  20. (*steve*)

    Driving a 12 pins LED display

    Have you ensured you have a common ground? I think that was a suggestion in what I think was the first part of this thread. I would have replied earlier, but starting a nee thread without a pointer to the old one meant I wad unsure what the first part was (and as I'm using a mobile device its...
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