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  1. Alec_t

    Connecting strobe light to 12V vehicle reverse lights

    Are you sure that's the correct method? That could be the cause of failure. A single-filament bulb generally needs only one supply wire and uses the vehicle chassis as the return conductor (ground). Two supply wires would be appropriate for a twin-filament bulb. Post a sharp well-lit picture of...
  2. Alec_t

    How to control the speed of a 24vdc pump from circulating water temperature?

    You may get away without shielding if you connect a capacitor (try 100nF) across the thermistor terminals at the pcb end to shunt away any noise pickup. The circuit should be responding only to slowly varying input. Soldering the cable end connections is probably best IMO, but the cable also...
  3. Alec_t

    Connecting strobe light to 12V vehicle reverse lights

    Welcome to EP! As we don't know what circuitry is inside the flasher unit it's difficult to say. The respective pair of wires going to each connection point (e.g point 1) on the unit seem to short out the lamp supply. Is the 'strobe light' in your thread title the flasher unit, or is it...
  4. Alec_t

    Making prison safer...

    If you made it strong enough to survive the mechanical abuse it would undoubtedly receive, then some idiot would find a way to hang themselves with it. Don't think the authorities would be too pleased having to deal with the inevitable Enquiry and bad publicity that would trigger.
  5. Alec_t

    Light controller circuit

    The resistor itself looks ok, but the board below it (second pic) looks cooked, so clearly the resistor has been getting very hot for some time. Its soldered connections don't look too happy though.
  6. Alec_t

    Colpitts generator Pspice

    C3 is 1000p in the schematic, but only 100p in the sim. Is that intentional?
  7. Alec_t

    Simple Motor Controller Circuit

    For best noise suppression you may need both.
  8. Alec_t

    How to control the speed of a 24vdc pump from circulating water temperature?

    Oops. My bad. Well caught.
  9. Alec_t

    How to control the speed of a 24vdc pump from circulating water temperature?

    A 10k thermistor should be ok. You could probably use it in series with the existing pot. Here are two options, one of which should put the trigger point in the right ball park :
  10. Alec_t

    Constant current (or voltage) source WITHOUT semiconductors?

    Saturable reactor / magnetic amplifier?
  11. Alec_t

    How to control the speed of a 24vdc pump from circulating water temperature?

    With a bit of luck you'll see the value stamped or printed on the pot. If not, you could try using the Ohms range of your meter to measure (with no power on the circuit) the resistance between the two outer pins of the pot and, for confirmation, from the centre pin to each outer pin in turn...
  12. Alec_t

    Cheaper Source of Part#BT53

    Part of what? Is there any equivalent part you could substitute? Google thinks BT53 is an old Formula One racing car, or a part of Ireland :).
  13. Alec_t

    How to control the speed of a 24vdc pump from circulating water temperature?

    What is the pot resistance, end to end? As for mounting the probe, you could embed it in epoxy putty conformed to the pipe shape to make good thermal contact.
  14. Alec_t

    New board...need drivers

    :confused: Were you planning on telling us what it is and what it's supposed to communicate? A link to its datasheet would be helpful.
  15. Alec_t

    How to test a capacitor

    What do you mean by 'good condition'? It is relatively easy to measure capacitance, but not so easy to measure, for example, breakdown voltage of the dielectric or to detect intermittent internal faults.
  16. Alec_t

    Built circuit w/ timer IC connected to SHDN pin of a voltage regulator - not shutting down properly?

    I replied at AAC.
  17. Alec_t

    Simple Motor Controller Circuit

    The flyback diodes could be working hardest when the motor is first switched on, if there is intermittent brush contact with the commutator. Your specified PFETs are marginal for their power handling. I'd choose something with a lower Rds(on) rating.
  18. Alec_t

    Built circuit w/ timer IC connected to SHDN pin of a voltage regulator - not shutting down properly?

    That inverter is a CMOS one, so draws just a few micro-amps when pulling high or low, hence dissipates only a few micro-watts. In my book that's negligible, but I don't know what you consider "too much" power?
  19. Alec_t

    Li-ion charging circuit protector help

    Have you asked the seller for the info?
  20. Alec_t

    Effectively defeating PWM on Jeep Wrangler

    Don't you risk shortening the life of the LEDs if you bypass the PWM? It depends on the LED modules/drivers you're using, of course.
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