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  1. KrisBlueNZ

    Help with 74LS373N latch (Supernoob)

    Yes, I understand. As long as the circuitry that is driving the signals on the IDC uses 5V logic levels you should be OK. Edit: Is there a specific reason why you're using 74LS373s instead of 74HC373s?
  2. KrisBlueNZ

    Remote control using CD4532 chip??

    Hi there and welcome to Electronics Point. Can you upload the rest of your circuit? We need to know what is driving the 4532's inputs.
  3. KrisBlueNZ

    28 inch Monitor won't power on anymore

    Low ESR electrolytics are normally described as such; if the description doesn't mention low ESR, it probably isn't. But it's best to try to match the original components' ESR as closely as possible. So we need to know the brand and series of those original electrolytics. Can you post the full...
  4. KrisBlueNZ

    Fuse confusion?

    It's common for switching power supplies to fail due to a voltage surge. The fuse then blows, and replacement fuses also blow immediately. This is because semiconductor components in the power supply have failed and must be replaced. The failed component may be the bridge rectifier, but in my...
  5. KrisBlueNZ

    ESR Meter advise

    Your English is fine. I hadn't noticed any confusion. Good luck!
  6. KrisBlueNZ

    Help with 74LS373N latch (Supernoob)

    No, you always have to provide a signal level. Don't rely on the inputs floating to any particular state, because they usually don't. TTL/LS is the exception; it's an old logic family, and its inputs float high, which is not what you might expect, and it's the reason that you should connect the...
  7. KrisBlueNZ

    Adjustable brightness torch??

    C1 is 0.1 µF and C2 is 0.01 µF. Actually the value of C2 isn't important; they can both be the same. Suitable part is http://www.maplin.co.uk/p/wima-metallised-polyester-pet-63v-01uf-capacitor-n20cn The dimmer you linked in post #18 would be OK. The 8A specification is just a maximum current...
  8. KrisBlueNZ

    Help with 74LS373N latch (Supernoob)

    The 373 is pretty straightforward and should behave like you want. The OC input is "output control" and must be low to enable the outputs. If it's high, the outputs go "tri-state", i.e. they float, and won't drive anything. The 373 is a transparent latch. While the G input is high, the outputs...
  9. KrisBlueNZ

    divided/2 transistorise frequency divider

    At 500 MHz? Mr. Bapi das, do you really require operation to 500 MHz?
  10. KrisBlueNZ

    Help Getting Started with PIC Microcontrollers

    The stack is a block of memory that is structured as a last-in first-out buffer, like a stack of cards, which the CPU uses to keep track of return addresses for calls to functions or subroutines. #include <stdio.h> static int n; void function1(void) { printf("One\n"); n = 1; } void...
  11. KrisBlueNZ

    Driving a relay from a PLC output

    As Frenoy said, that circuit should work, although it's good practice to add a resistor between the base and emitter of the transistor. In this case I would use a 10k resistor from the PLC output to the base (R1), and a 470Ω resistor between the base and emitter of the transistor. With the...
  12. KrisBlueNZ

    ESR Meter advise

    My comment was just that it should be possible to measure ESR independent of the apparent "resistance" due to reactance because the two are 90° out of phase with each other. This circuit applies a 100 kHz sinewave of 10V peak amplitude to a capacitor (ESR and C) in series with a current sense...
  13. KrisBlueNZ

    Dumb question re. simple inverter

    Oh sh*t Trevor! How did you break your spine?
  14. KrisBlueNZ

    Designing a Time Delayed Relay

    Thanks Steve! I should have looked for applications info from Tamura :-( That document you linked to says "An Inherently Limited transformer has designed into it an impedance that limits the current output to a maximum value. This coupled with the correctly sized transformer limits the...
  15. KrisBlueNZ

    Designing a Time Delayed Relay

    I see what you mean. I don't know what's the best way to approach this. I think there should be a fuse somewhere. I'll ask Steve for his opinion.
  16. KrisBlueNZ

    Dead Automatic Battery Charger for Autos. Please help me troubleshoot.

    Oh dear! You'd better re-check the Schottky double diode on the heatsink, as well as replacing the electrolytic again. Those voltages you measured on the transistor are not what I was expecting. Can you push the transistor over againt the board so its flat face is visible, and take a photo...
  17. KrisBlueNZ

    Promote a post!

    Good photo and explanation on reliably connecting crimped eyelet terminals to PCBs and using Loctite: https://www.electronicspoint.com/threads/loctite-on-electrical-connections.271446/ posts #4 and #6
  18. KrisBlueNZ

    Stage Line 500W amp repair project

    Good info there from Dave! There's also a good page at Wikipedia: https://en.wikipedia.org/wiki/Types_of_capacitor
  19. KrisBlueNZ

    Stage Line 500W amp repair project

    Yeah, I'm sorry about that. These days, you pay a price if you want to be responsible and sensible, and repair your old electronic equipment. Most people simply throw it away and buy a new, cheap, poorly made replacement (unless they're wealthy enough to buy a properly made replacement). It may...
  20. KrisBlueNZ

    Trail Camera No Flash Troubleshooting

    That's interesting debe. According to the phase dots, that circuit is operating in forward conversion mode, i.e. the load (D1) current flows while the switch is ON, rather than flyback mode, where the load current flows when the switch is OFF. Is that normal for these circuits? I would have...
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