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  1. KrisBlueNZ

    Convert Wireless PIR sensor to use power supply instead of Batteries

    Yes they should be fine. Much more than you need, but you won't need to do any soldering. You'll need an input voltage at least 2V higher than the output voltage. I would use a 6V "wall wart".
  2. KrisBlueNZ

    Potentiometer Burnout

    I find it hard to follow that schematic... too much like a grid of wires, and not many components. Maybe you could compact it a bit, and move components around so there's not so much zigging and zagging? And group wires together by using different spacings? And keep important signals (AGND for...
  3. KrisBlueNZ

    LED optic sensor circuit

    Some of the reviews on the RS site said that too. Maybe :-) The way to be sure is to watch the LED using a cellphone camera, and trying both components, both ways round, with a 220 ohm limiting resistor. Only the LED will emit light, and it will emit light only when connected the right way...
  4. KrisBlueNZ

    IR proximity sensor

    Have a look at this brief teardown of a Glade sense-and-spray unit: http://www.jcopro.net/2011/02/09/glade-sense-and-spray-teardown/ He says "I don’t think the “proximity sensor” on the Sense and Spray works as one would expect. After reading the back of the box, it seems to work on sensing...
  5. KrisBlueNZ

    Convert Wireless PIR sensor to use power supply instead of Batteries

    Hi Naynesh and welcome to Electronics Point :-) You need two voltage regulators. Your best option is a member of the LM317 family. These are three-terminal devices that will drop a DC supply voltage (e.g. 6V from a "wall wart" adapter) down to the voltages you need. The output voltage is set by...
  6. KrisBlueNZ

    What happens when an AC powered floor-fan dies?

    Well, that's the most important thing to know about it! OK. I very much doubt that there's any problem at all. You're welcome my friend :-)
  7. KrisBlueNZ

    What happens when an AC powered floor-fan dies?

    Hi there and welcome to Electronics Point :-) I like your quote. But I don't like your username. You don't sound like a stupid fella to me. I think it's fair to assume that your fan overheated. This could have happened because the lubrication dried out, or for other reasons. I have little...
  8. KrisBlueNZ

    Rectifier value?

    OK, it sounds like that amplifier has a switching power supply. Any bridge in a suitable package, that's rated for 4A or more, and 600V or more, should be suitable. The KBL, KBU, and RS-4L packages look like a match, but you'll have to check yourself, because I can't tell the exact size from the...
  9. KrisBlueNZ

    LED optic sensor circuit

    Yes, exactly what Steve said. Cellphone cameras (all digital cameras) respond to infra-red light, so you'll be able to see the IR LED glowing when you get it round the right way. I think the phototransistor has its leads reversed in those recent pics. The flat section on the skirt is probably...
  10. KrisBlueNZ

    Evaluating a cap. power supply in LTSpice

    Yeah :-) Another way of saying this is that the ratio (r) between a value (n) and the value after it (n+1) is equal for every value. So for E6: start = 10 10 * r = 15 15 * r = 22 22 * r = 33 33 * r = 47 47 * r = 68 and then 68 * r = 100 to get to the next decade. So you can calculate the ratio...
  11. KrisBlueNZ

    LED optic sensor circuit

    OK, there's a problem: the voltage on the anode of the LED cannot be 4.3V as you've shown in the diagram. My guess is that you have the LED and the phototransistor exchanged. That could also explain why you measure 0.5V on the phototransistor collector. The photos of the pipe look OK. I assume...
  12. KrisBlueNZ

    Potentiometer Burnout

    That schematic is too small to be readable...
  13. KrisBlueNZ

    LED optic sensor circuit

    One of the resistors is connected wrong. Both of them should have one end connected to the +5V rail. You need to find out which device is the LED and which is the phototransistor. If you have a cellphone with a camera, it will "see" the infra-red light. Try both devices in the left hand...
  14. KrisBlueNZ

    Light powered LED circuit

    Hi Nick and welcome to Electronics Point :) You need some kind of oscillator. There are many options. But I don't think your project is feasible. First, photovoltaic cells are not very efficient and cannot generate much power unless (a) they are very big, and (b) they are in direct sunlight...
  15. KrisBlueNZ

    PWM output mirror??

    Yeah, I wondered. Sarcasm doesn't work well in a text medium. That's why we have emoticons :-) I got the impression that the drive signal changes when he changes the load. Which of course it should. I don't like it when people post a vague question then disappear. It leaves us guessing, and...
  16. KrisBlueNZ

    need to identify this capacitor

    MOV = metal oxide varistor. They do fail if there's a power surge (e.g. a lightning strike nearby) but when they fail, it's usually pretty obvious - chunks missing, scorch marks, etc. That one in the photo looks like it has led an uneventful life so far. I don't think a multimeter test would be...
  17. KrisBlueNZ

    Rectifier value?

    Hi Joe and welcome to Electronics Point :-) You can get an idea of the voltage rating of the rectifier by looking at the voltage rating of the big electrolytics that are connected to its output. It's probably a split supply, so double the voltage rating of the electrolytics and add another 50%...
  18. KrisBlueNZ

    PWM output mirror??

    I don't think so. That schematic is a buck regulator, and the switch is a MOSFET. But without an actual schematic of the circuit, and some answers, who knows!
  19. KrisBlueNZ

    LED optic sensor circuit

    Yeah. It's pretty funny looking through all the different opinions. In my limited experience, IR LEDs are normally water clear, and IR phototransistors are normally tinted. But the Everlight LED from Digikey that I recommended is apparently tinted blue. The matching detector is tinted dark...
  20. KrisBlueNZ

    help out regarding adc

    Kindly use Google to search for information that is already out there. This will save time for all of us. We don't even know what to look for, since you haven't given any information apart from "ADC". We know about ADCs but there are lots of them and they're used for lots of different things...
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