Search results

Search Forums New Posts
  1. (*steve*)

    Help with battery powered PC case fan

    I think its to reduce electrical noise. The best solution would be to connect the fan blades to a mouse wheel and insert a well fed mouse. "Best" refers to low amounts of electrical noise :D I'm interested in some of the language used to describe the power supply. Other than using toroidal...
  2. (*steve*)

    Help with battery powered PC case fan

    A small 12V lead acid battery would probably be the best bet then :)
  3. (*steve*)

    Help with battery powered PC case fan

    And the pedalboard (the penny just dropped as to what it is) is powered from the mains? I would just use a small mains operated 12v plugpack (wall wart).
  4. (*steve*)

    help/advice for small wind turbine installation

    One option is to have the windmills charge a battery and the batteries power the sculpture *if* the batteries are sufficiently charged. As for motors, it depends what you're doing. Almost certainly you'll want slow movement, and that means stepper motors or gearing. Stepper motors are harder...
  5. (*steve*)

    Help with battery powered PC case fan

    Does the pedalboard have a power supply? I guess I'm confused, but you said you wanted to cool it, so I assume it is powered (or powers) something.
  6. (*steve*)

    Reading PIC ports

    The code in post 5 looks good to me, and should be very time efficient as it has unrolled the loop(s). It may not be space efficient. I didn't check to see if the port is read once at the beginning of if each bit is tested "live" from the port. In the latter case there is a potential problem...
  7. (*steve*)

    BC147 transistor equivalent

    NTE123AP
  8. (*steve*)

    Help with battery powered PC case fan

    What power do you have available? If you have 12V, that would be perfect. If not, a small regulator may be better (to convert the voltage) rather than adding another battery.
  9. (*steve*)

    Wi-fi

    The best thing to do is simply to google for diy WiFi antennas.
  10. (*steve*)

    Part required or is another suitable

    Sorry, yeah, the last pin. I'm stuck on a phone at the moment and I'm doing it by memory.
  11. (*steve*)

    Trying to make a transistor cancel another transistor

    Sure, you just turn it on it's head. Essentially, swap the power supply pins and turn the LEDs around.
  12. (*steve*)

    impose current ceiling

    Current limiting can cause you to need to dissipate a lot of heat. When I first read the title of your thread, a constant current circuit seemed to be the answer, but after I read what you actually needed to do this was not a solution I was going to suggest.
  13. (*steve*)

    Part required or is another suitable

    Yes, you can solder a thin wire from one of the red arrow points to pin 6. Pin 7 is also critical as it is the ground connection (I.e. A power supply pin) of the chip. The others didn't look important from memory. My concern is that you may not have the skill to do the fine work required...
  14. (*steve*)

    Multimeter giving bad voltage readings

    Just out of interest @shrtrnd. If you had to calibrate a voltage source (lets just say you were just going to measure and report the voltage) of say 10V, how precise could you practically measure it (lets assume it was limited by your equipment rather than noise or drift on the source itself)...
  15. (*steve*)

    Trying to make a transistor cancel another transistor

    If you were really keen you could drive the NTC thermistor from a constant current source, buffer the voltage with an emitter follower, use this to drive a series of long tailed pairs comparing the voltage to a reference and driving a LED. You would use a shed-load of transistors in almost...
  16. (*steve*)

    Part required or is another suitable

    When you replace the chip, you will need to use fine wires to connect to the pins where pads have been removed. Pins 6 and 7 seem to be the main ones involved.
  17. (*steve*)

    Promote a post!

    Desoldering the easy way using a technique I've not seen before. https://www.electronicspoint.com/threads/designing-a-time-delayed-relay.268425/page-20#post-1703843
  18. (*steve*)

    need help from GC-eDRAMs experts

    I just assumed he was testing DRAM using a really good pianist.
  19. (*steve*)

    NPN transistor as switch for LED problem

    I believe it is possible to produce doped channels across the base. These produce a resistive connection between emitter and collector without significantly affecting the base-emitter or base-collector junction. Apparently this results in increased leakage, but with transistor action still...
  20. (*steve*)

    need help from GC-eDRAMs experts

    1) increase the time until data starts getting corrupted. 2) decrease the time until data starts getting corrupted. Note that testing for data corruption is non-trivial. You need to test worst case patterns where nearby 1 cells leak into a 0 cell and give versa. This requires intimate...
Top