Search results

Search Forums New Posts
  1. KrisBlueNZ

    Designing a Time Delayed Relay

    The incoming power requirement (into the transformer) is tiny. Your wires just need to be insulated to safety standards, and thick enough to be strong enough not to break. The current paths you're monitoring and switching are a different story. Personally I would probably use stranded wire of...
  2. KrisBlueNZ

    help me quickly: diode curves question

    First of all you need to understand that a diode doesn't have "resistance" as such - it's a diode, not a resistor. All you can meaningfully say about it in terms of resistance is that it has a characteristic called "small-signal resistance", also called "incremental resistance", "dynamic...
  3. KrisBlueNZ

    How to Step up Voltage? DC to DC converter or Op Amp

    Yes, as shown, if you have a 9V supply. If you want to avoid the 9V supply, you can get most of the 0~5V range but you'll need to use a different op-amp. Clockwise and counter-clockwise directions for the preset potentiometer (trimpot). So that turning it clockwise will increase the sensitivity.
  4. KrisBlueNZ

    new here, H-bridge frustrations...

    Hi there and welcome to Electronics Point :) There are lots of H-bridge ICs available, with internal or external switches. Many of them are SMT so you should decide, then tell us, whether you want to go in that direction. Digi-Key is always a good place to start when you're looking to see...
  5. KrisBlueNZ

    What cable/wiring to use with electret condensor mic

    Stereo or twin, screened or shielded, audio cable. It has two separately insulated cores inside a woven wire screen. Have some links...
  6. KrisBlueNZ

    Stage Line 500W amp repair project

    Also can you confirm that all components are installed as normal except: All four output transistors not installed All four fuses replaced with resistor fuses made with fusible resistors and LEDs
  7. KrisBlueNZ

    Stage Line 500W amp repair project

    OK, sorry for the delay. I'm confused about the voltage readings from post #101. You set your multimeter to the "2000m" range in the VDC section? That means it measures voltages up to 2000 mV, or 2V. Does that sound right? So those figures, like "021" for the voltages across R62 and R71, those...
  8. KrisBlueNZ

    4 channel timer board help.

    Hi there and welcome to Electronics Point :-) Something like an Arduino with a relay output "shield" would be a ready-made and reasonably easy-to-use solution. Some programming required but there will be similar existing projects that you could use as a starting point. Capable of much more than...
  9. KrisBlueNZ

    Oscilloscope ROLL mode used for?

    OK I'm closing it now Danny
  10. KrisBlueNZ

    Buzz In Portable Cassette Player

    Do you still have continuity from the metal chassis to the 0V rail of the circuit?
  11. KrisBlueNZ

    voltage comparator

    Hi there! I found the project at http://electronicsproject.org/safety-guard-for-blind/ Most of the circuitry shown in the receiver section is not needed! The TSOP1738 infra-red receiver/demodulator already contains all of the required signal processing, and produces a clean logic-level output...
  12. KrisBlueNZ

    Trying to fit a grounding wire on my PL-Z81 turntable?

    Hi there Pierce and welcome to Electronics Point :-) Ideally the grounding wire should be connected to the power amp, not the preamp. If you connect it to the preamp, any current that flows through it will flow through the wires that carry the signal from the preamp to the power amp, and could...
  13. KrisBlueNZ

    Buzz In Portable Cassette Player

    Gryd3 asked you for some photos
  14. KrisBlueNZ

    Oscilloscope ROLL mode used for?

    Have you tried http://www.google.com/?gfe_rd=cr#q=oscilloscope+roll+mode
  15. KrisBlueNZ

    HELP!!!! Can't find parts

    Did you try Googling that part number? I did. Here's the first result: http://mouser.com/ProductDetail/Omron-Electronics/G8P-1A4P-DC12/?qs=Rh%252baoYk36r7RCFqGn7h4TA%3D%3D
  16. KrisBlueNZ

    Heatsinks for very hot Xbox Chips

    I'm closing this thread now
  17. KrisBlueNZ

    Adjustable brightness torch??

    Sure, you can get them via eBay. You're more likely to get stung by a counterfeit though. (Yes, counterfeiting is a growing problem in the electronics industry - see http://sound.westhost.com/counterfeit.htm for some good information.) Any N-channel MOSFET with a current rating of at least a...
  18. KrisBlueNZ

    Heatsinks for very hot Xbox Chips

    Danny has asked me to reopen this thread. He thinks other users may have more to add. He doesn't have any other threads open, so I think that's reasonable.
  19. KrisBlueNZ

    Ohms

    The diode test range is good for: Determining whether the transistor is a PNP or an NPN (and also checking that it is a bipolar junction transistor - it might be a FET or something else); Determining which lead is the base; Diagnosing the most common fault: a short between two or more terminals...
  20. KrisBlueNZ

    Stage Line 500W amp repair project

    OK, then don't remove the resistor. Why did you remove the resistor? I never suggested that. Why are you surprised if something odd happens when you remove the resistor?
Top