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  1. KrisBlueNZ

    Constant Current Power Supply

    You could ask them that question. I'd be interested to see their reply. That company does seem to be very focussed on marketing and hype. Perhaps the extra cost is in the pure gold core inside the company logo on the front of the power supply?
  2. KrisBlueNZ

    LED Flasher help.

    1. OK, the second photo in your last post shows a hacked CD-ROM drive with nine LEDs in it. You said earlier that your circuitry goes in the CD-ROM drive case, so I guess these are the LEDs in the left part of the diagram, correct? 2. Your diagram shows five LEDs in the left section, but there...
  3. KrisBlueNZ

    LED Flasher help.

    OK... Now, what are the red lines supposed to mean? An "extra shared circuit"? Can you draw what you actually have? You've done a good job with the other LEDs.
  4. KrisBlueNZ

    Constant Current Power Supply

    Nice work Bob! Literally a valuable post!
  5. KrisBlueNZ

    Stop circuit when battery drops below 3v?

    Thanks, and yes it's a pretty impressive component. That's true if you're talking about long-term heating, but there's also safe operating area and short-term heating to consider. If the load draws 1A and can be approximated as a 3 ohm resistor, worst-case dissipation will be half-way through...
  6. KrisBlueNZ

    Stop circuit when battery drops below 3v?

    OK, if your circuit is battery-operated, you can break the circuit in either the negative or the positive connection, right? So you could use an N-channel MOSFET to interrupt the negative line? There's a company called Alpha & Omega that make some amazing MOSFETs that achieve VERY low...
  7. KrisBlueNZ

    Variable power supply

    Have you read the thread that Fish linked to in post #2 on this thread? The important characteristic you need is high current. A few volts will be enough, unless your wire is very long and/or has a very high resistance. BTW if you can get different grades of nichrome wire, go for one with...
  8. KrisBlueNZ

    LED Flasher help.

    Hi WaterWalker, Thanks for making an effort to clarify things. Criss-crossing wires is no problem. Unfortunately that schematic is still not clear. You seem to have five groups of LEDs at the bottom right, identified with three symbols - square, diamond and star. Then you have three...
  9. KrisBlueNZ

    Need help with a PSU schematic

    That schematic looks really good now. Your comments are good. I noticed that the "C12" line is missing a final "V" for volts, and the correct manufacturer's name for IC1 and IC2 is "ON Semiconductor", i.e. with a space after "ON", and no final "s". The layout looks nice too. I still think you...
  10. KrisBlueNZ

    6 CELL LI-ION 22.2V BATTERY LEVEL MONITOR

    Even if the voltage is wrong, you can still test the circuit. Once it's working properly and you get the three different colours, you can worry about setting the actual threshold voltages exactly.
  11. KrisBlueNZ

    6 CELL LI-ION 22.2V BATTERY LEVEL MONITOR

    You should be able to test using a couple of 9V PP3 batteries in series. You won't be able to get the threshold exactly right, but 18V is about right, isn't it?
  12. KrisBlueNZ

    Philips DS 9000 no power

    I don't think shrtrnd meant it as a joke... shrtrnd, if you haven't got the joke yet, look at the first three words of the first sentence of your post #2 in this thread :-)
  13. KrisBlueNZ

    LED Flasher help.

    I'm afraid that description is far too vague for me to follow confidently. It sounds like you have a number of red LEDs, a number of blue LEDs and a number of white LEDs, and you have arranged for circuit D to drive them all, while circuits A~C only drive one set each. The diagram of the LED...
  14. KrisBlueNZ

    Need help with a PSU schematic

    I don't see any need for D3, D4 and D6. You should probably have a reverse diode across IC4 the way you have for the other three regulators. You're missing dots on various junctions. Most of them don't matter, but the wire that runs from R6 to D5 needs a junction on it, otherwise it looks like...
  15. KrisBlueNZ

    DC Controlled AC Load

    Right. Some SSRs are probably approved by UL Labs and other safety organisations too. True, a mechanical relay has practically no leakage. That SSR you just found seems to have a leakage of 100 µA which is pretty low, but you're right, it's a consideration. You could add a resistor across the...
  16. KrisBlueNZ

    Where is Electronics Point based?

    Dallas, Texas, huh.
  17. KrisBlueNZ

    Where is Electronics Point based?

    I was just wondering. There are members from lots of places, including England, America, and perhaps disproportionately, Australia. What country is Electronics Point based in?
  18. KrisBlueNZ

    555 timer HELP

    Their advice is all good. Most of it agrees with my advice, just worded slightly differently. I think the problem is that you are not reading this advice carefully. You've told them a lot of things that you should have told us earlier. You didn't tell us that you were powering the circuit from...
  19. KrisBlueNZ

    DC Controlled AC Load

    Yes, that SSR looks good. A bit overkill, but for a one-off project the extra cost isn't important. The 1.4V control voltage is not "not ideal". It's just the forward voltage of the LED. There's nothing unusual or problematic about it. You just need to drive the LED inside the SSR like a normal...
  20. KrisBlueNZ

    555 timer HELP

    Open wide, here comes the train :-)
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