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  1. Fish4Fun

    Noob making a power supply

    giser3546, I am all for learning oriented projects.....I constantly strive to invent one type of wheel or another.....You might consider learning about power supplies by starting with a simple constant-current Buck Converter to drive LEDs....Lot less collateral damage when something goes wrong...
  2. Fish4Fun

    Help with a LED driver

    AtomV2, The Data Sheet you linked states the Vf is 3.6V to 4.3V with a Max of 5.5V (Not exactly certain what the "Max = 5.5V" is all about......but anyway)...nominal current is 30mA while Maximum pulse current is 80mA..... It would likely be a good time to give a little bit of information...
  3. Fish4Fun

    Been doing it all wrong!!

    Martaine2005, I think you and Gryd3 are on different pages...though he is obviously correct on the arithmetic side of your math problem(s). I think what you are asking is about subtracting the LED Vf from the supply Vf prior to figuring the resistance? ie: Typical Specs for a 1W White LED...
  4. Fish4Fun

    Noob making a power supply

    giser3546, At the risk of sounding lazy.....why wouldn't you just order a power supply designed for it? I am as hard-headed and cheap as they come, but for less than $11 you can get a brand new one delivered.....Not sure what the import duty to Ca would add, but even if it is 100% you are...
  5. Fish4Fun

    Need help design UV Curing heads

    Hey David...... These are available from a US supplier....quite a bit more expensive than China direct.... http://www.ebay.com/itm/3W-365nm-UV-LED-ultraviolet-LED-chip-light-High-Power-bead-with-20mm-pcb-/301529942113?pt=LH_DefaultDomain_0&hash=item463495c861 These are also available from...
  6. Fish4Fun

    Need help design UV Curing heads

    Hey David, There are a bunch of choices in 365nm LEDs ranging from a few mW right on up to 100W....I don't have any experience with UV LEDs, but I have a fair amount of experience with LEDs in general....Working on the assumption that UV LEDs are similar to other LEDs, first thing I would...
  7. Fish4Fun

    Sensorless BLDC motor driven synchronously.....hrmmm...

    Hey CDRIVE thanks for the input! "logical physics".....perhaps....but not the way I am looking at it (which very well could be wrong) ....if it were a brushed DC motor then as torque is added the rpm should drop and the current should increase...perfectly logical....from the perspective of...
  8. Fish4Fun

    Sensorless BLDC motor driven synchronously.....hrmmm...

    Hey Adam! Sorry for the silent period.....work and life have once again proven that time-sucking-vortexes are not only real but prevalent. I haven't done any further testing, so I will explain the "theory" of operating w/o feedback....When a stator field is energized a magnetic field is...
  9. Fish4Fun

    Sensorless BLDC motor driven synchronously.....hrmmm...

    Hey Adam! While I assume YOU understand 'how' a traditional synchronous 3-Phase motor operates, I think this may be causing more confusion than illumination.....obviously if the BLDC motor were strictly behaving as a traditional 3-phase synchronous motor then it would more closely manifest the...
  10. Fish4Fun

    Make a DC supply?

    Hey JFS-Chatt! My wife is a teacher, so I know more than a few teachers.....none of the local schools offer anything in the way of electronics, which I think is shameful, but I have certainly considered various approaches to getting kids interested in electronics.....A lot depends on how much...
  11. Fish4Fun

    Sensorless BLDC motor driven synchronously.....hrmmm...

    k, so just playing around, I wondered what would happen if I decreased the "dead time" and allowed all three phases to be active simultaneously as follows: | A | B | C | | A | B | C | | EN | Ip | EN | Ip | EN | Ip | Hex...
  12. Fish4Fun

    Sensorless BLDC motor driven synchronously.....hrmmm...

    Hey Adam....Thanks for the continued interest! I will draw up a schematic at some point, but it is really straight-forward.....three Full H-Bridges with "High", "Low" "Disable" inputs....One Full H-Bridge connected to each of the three stator coils.....The switching sequence is as follows...
  13. Fish4Fun

    Sensorless BLDC motor driven synchronously.....hrmmm...

    Hey Adam! I am a bit unclear what you mean by the above....By definition synchronous implies an AC signal, in this case a psuedo-three phase ("Trapezoidal-Three-Phase") AC output from discreet H-Bridges states....the rotor magnets absolutely DO follow the resulting stator fields....for higher...
  14. Fish4Fun

    Using a CNC router for designing PCBs

    Quibix..... CNC routers are a hobby unto themselves :-) ....but it is not a cheap hobby.....I have seen some build threads where people salvaged most of the parts from old printers and the like and claim to have less than $100 in what appears to me to be a fairly decent machine, but IMHO the...
  15. Fish4Fun

    Sensorless BLDC motor driven synchronously.....hrmmm...

    So I have been playing with some small sensorless BLDC motors (hobby small, not industrial small, lol)......I have read tons of white papers and application notes and certainly understand the how and why of sensing the zero crossing point and all of the caveats, foibles and pitfalls...
  16. Fish4Fun

    Lab power supply from microwave transformer project.

    @Damien... YES. I mean no disrespect, but you should absolutely "go back to low voltage stuff". Regulatory laws, rules, codes and ordinances are in place to protect life and property, circumventing those safeguards without certain knowledge of the ramifications is a fools errand with...
  17. Fish4Fun

    Using a CNC router for designing PCBs

    Hey Qubix, welcome to EP! The answer to your question is absolutely, maybe, kind of, sort of, yes. I have made a lot of PCBs using my CNC routers...there are some things they are great at and some things that they are not so great at....like all things there are trade-offs. What they are...
  18. Fish4Fun

    Thoughts on the Turing Test.....

    Turing....well I have been getting that one wrong for 20+ years, LOL....dyslexia is such an odd thing. CSR = Customer Service Representative.....Yes, sorry, should have clarified.... Obviously a bot serving in a CSR role is not generally being "tested"; however, I am not certain that...
  19. Fish4Fun

    Thoughts on the Turing Test.....

    So we are all clear: So, in a casual conversation about an online entity, I suggested that perhaps the entity was a "bot" that could manage a few rounds of a Truing test, and someone stated: Obviously the statement is True, but in the process the underlying question becomes, "How many...
  20. Fish4Fun

    Dell Laptop Touchpad......

    Well I will be a suck-egg mule! After battling the touch pad issue since Friday....I finally made the command decision to swap the touch pad out with one from an E6500...well guess what....the E6500 touch pad isn't the same size as the M4500....who'd have thunk it? Good news I discovered this...
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