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  1. chopnhack

    "Has it got the Cobalt?" (story)

    LOL, certainly a blast from the past! Pascal/Fortran was around when I was young in school, but they thought better to just give us Basic :-)
  2. chopnhack

    V-Reg Board for Breadboard use

    I see the error now! Will the circuit not work with a NPN transistor or would it have to be wired differently? Also, could you explain how the voltage potential stays regulated when there is access to the input v. pot. through the transistor ?
  3. chopnhack

    V-Reg Board for Breadboard use

    Thank you Harald :-) So, the base and collector of a NPN transistor are in parallel to the series resistor of the circuit, the small current produced across the resistor turns on the base allowing current to flow across the collector through the emitter to the output side of the regulator...
  4. chopnhack

    Can wall wart's be damaged by diodes?

    Its very possible. I have had this one LED running now for nearly 2 hours and the voltage has held steady to within 0.02V. Its such a small load though, I am looking at wiring a group of LED's in parallel, IIRC that uses more current at the same potential. I will have to review whether the...
  5. chopnhack

    Buying ICs off of ebay - I think I finally learned my lesson

    LOL, never, ever trust some guy in Oklahoma! :p:D
  6. chopnhack

    Can wall wart's be damaged by diodes?

    Very good point Steve! The kids and I were playing with snap circuits - childrens electrical activity center and I was just telling them that this morning! Check your picture to make sure you have everything connected first!! Do as I say, right? I left the transformer powering a LED for about...
  7. chopnhack

    Can wall wart's be damaged by diodes?

    No schematic as it was a simple circuit from the barrel connector through a resistor to the LED, I had already broken down the breadboard to create a different circuit to test the LED - which is working fine, that is what confused me! I would have to agree, somehow the w.w. got shorted or...
  8. chopnhack

    Buying ICs off of ebay - I think I finally learned my lesson

    You scared me Supercap, I just invested a whole buck in some v-regulators :D:p
  9. chopnhack

    Can wall wart's be damaged by diodes?

    I was using my w.w. to power a breadboard and didn't notice that one of my jumper wires was in the wrong location. The LED did power up, but the light gradually diminished. I disconnected and found the misplaced jumper, but instead of having 16.4v I now only had about 2v. Any ideas of how that...
  10. chopnhack

    Constant current power supply

    Do you have a schematic of your changes? Some voltmeters may require a reference voltage outside of the circuit to function properly.
  11. chopnhack

    V-Reg Board for Breadboard use

    Yay! Thanks for the replies guys. I misquoted the IC, it is in fact a to-220 LM7805. A good deal on ebay, I believe, @ 10 for 0.99 cents delivered :-) I don't know what the max current draw will be, but I could always label it as a max of 100mA for now and see if I ever need more. For the...
  12. chopnhack

    V-Reg Board for Breadboard use

    I salvaged a wall wart as well as the matching barrel jack from an older wireless router and wanted to make a small board to attach to my breadboard for a "benchtop" power supply until I get to that more advanced project ;-0 Should I use the 78L06 instead of the '05 if I want to make sure I...
  13. chopnhack

    Designing a Time Delayed Relay

    No real progress yet, I received some small parts in the mail and they have kept me preoccupied (actively toying with them :D). Never owned a breadboard before! Kris, what is the purpose of Q1? When the base of the BJT has potential across it, the gate opens and there is flow from the collector...
  14. chopnhack

    Designing a Time Delayed Relay

    Thanks Kris, the board was a very rough draft, I was throwing things together to see what space constraints we had to work with. I remember point 1 about the high voltage being isolated, thank you for the reminder and the layout tips! As you see I will need them :-) The dotted line is actually...
  15. chopnhack

    Designing a Time Delayed Relay

    A lot to be desired, but at least with so many common 0V connections, the board can make use of a "ground" plane.
  16. chopnhack

    Simple PWM LED Driver than randomly dims/brightens?

    Linear feedback shift register, very clever! I think that would be a 74 series logic chip? I may have seen one of those in my travels on the web. Pretty cool to be able to use a LED to act as a light detector! I didn't find the link you were referring to, but I did find this one...
  17. chopnhack

    Simple PWM LED Driver than randomly dims/brightens?

    A rather enlightening (no pun intended) few hours of web browsing shows that the easiest way to achieve my goal is to actually purchase "flickering" leds! Who knew? Apparently the chip to control the flickering is self contained right inside the epoxy dome of the LED. Wiring other LED's in...
  18. chopnhack

    Simple PWM LED Driver than randomly dims/brightens?

    Is there a simple way to construct a dimmer circuit for LED's that randomly dims and brightens without resorting to higher level digital products? I need to power three green LED's in series, preferably driven by a 9V battery. Current requirements of the LED's are 20mA with a 2-2.2Vf drop. I...
  19. chopnhack

    PCB Printing

    GIF files are simple images of the layout, they do not have the necessary data to construct a pcb like drill hole size, solder masked areas, etc. You can use it as a reference, but you would have to construct industry standard Gerber files with the relevant data for them to construct your...
  20. chopnhack

    Designing a Time Delayed Relay

    I have an initial layout, but it looks pretty rough... The good news is that two 8 pin headers will fit!
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