Search results

Search Forums New Posts
  1. KrisBlueNZ

    Distressed Nerd - How to increase Motor RPM?

    Yeah I like variacs too. I guess the high price is just because they're a niche product nowadays.
  2. KrisBlueNZ

    8051 programming in c

    Try clicking here first. If you're after information specifically on the MIDE 51 IDE and compiler, try: http://mcu-programming.blogspot.com/2006/09/installing-mide-51-and-sdcc-and-for.html http://mide-51.software.informer.com/0.2/ If you have a specific problem or question please ask it directly.
  3. KrisBlueNZ

    ad5422.h do you have it...

    Are you looking for a file called ad5422.h? Is it this one you want? https://github.com/cyceron/TML/blob/master/ad5422.h
  4. KrisBlueNZ

    Distressed Nerd - How to increase Motor RPM?

    Variacs are big and expensive. I'd suggest an off-line switching power supply with adjustable output voltage. I agree with everything else though!
  5. KrisBlueNZ

    Help identify a component

    That part does look like an SMT resistor, but a marking of "2200" means 220Ω not 2200Ω. The four-digit marking system uses the fourth digit as a "multiplier" which tells you how many zeros to add, with the answer in ohms (Ω). So for example: "1782" = "178" then 2 zeros = 17,800Ω = 17.8 kΩ...
  6. KrisBlueNZ

    power supply design help

    In formulas, "I" (current) is always in amps. Your current is 100 mA, which is 0.1 amps. You should start by rearranging the equation so it tells you the number you want to know, which is C. Vripple_peaktopeak = I / 2 f C therefore C = I / (2 f Vripple_peaktopeak) You know I and f, but what...
  7. KrisBlueNZ

    Sony Receiver STR - DA555ES Displays "protection fan" when turned on.

    Sorry for the slow reply! If the fan works when powered externally, it's not likely to be the problem. There will be some tests you can do with the fuse blown, but we have to fix the problem that is causing the fuse to blow. I've got the service manual but it's not complete. It does show the...
  8. KrisBlueNZ

    Phase voltage circuit help

    Or if you're sampling many times per cycle, you could omit the smoothing capacitor and your DAQ would see the actual peak voltage for each of the three phases in sequence. You might not be able to tell which phase was which, without some other synchronisation method.
  9. KrisBlueNZ

    Sony Receiver STR - DA555ES Displays "protection fan" when turned on.

    Maybe. And maybe it's the fan. You could try unplugging it, if it's unpluggable. I'm just downloading the service manual now and will post again soon.
  10. KrisBlueNZ

    Transformer/Coil

    Kavin. I'm very forthcoming and helpful with people who co-operate! The thing is, I asked those questions because I think the answers could help me understand your requirements better, and provide more appropriate answers. I see a great deal of time wasted on these forums when people answer...
  11. KrisBlueNZ

    Transformer/Coil

    It's not obvious that the relay is being used to discharge the capacitors because you don't show what it is connected to! Actually you have shown it in series with the capacitors, not in parallel. Here are the questions from previous posts that you have not answered. Where did you get the...
  12. KrisBlueNZ

    Transformer/Coil

    Answer the rest of my questions and I'll start answering yours!
  13. KrisBlueNZ

    Phase voltage circuit help

    Throw me under the bus why don't you Adam :-) Looking back on this thread, I don't think I even understood the question. As far as I can tell, you seem to want to monitor the voltages on three phases going to a motor, but you only have a single pair cable between the motor your DAQ. Is that...
  14. KrisBlueNZ

    8051 timer in assembly

    Hi there and welcome to Electronics Point. The 8051's timers are well-documented in lots of places. Have you done a Google search? That should be the first thing you do. When I did it, I found a lot of good explanations: http://www.8052.com/tuttimer.phtml...
  15. KrisBlueNZ

    Modify circuit to add switch and timer

    That's a valid complaint but posting a useless response isn't going to help. The OP only gets notified of the first response on his thread after each time he visits the site. If you really must, you could post a teaser, outlining the basics of your suggestion, and asking the OP to come back and...
  16. KrisBlueNZ

    Transformer/Coil

    That circuit is a DC-to-DC inverter. The input is DC (from the 36V battery) and the output is DC (after rectification and tripling). The transformer operates using AC, as all transformers do. The transistors at the left convert the DC from the battery into AC to drive the transformer, and the...
  17. KrisBlueNZ

    Proper Usage of Oscilloscope (40 Marks)

    Right! Yes. Set it to AC and zoom in until the AC component nearly fills the display, so your estimate of its amplitude will be as accurate as possible. The scope will probably display the amplitude as a number as well. But you don't need to find the centre of the waveform - you only do that...
  18. KrisBlueNZ

    Designing a Time Delayed Relay

    OK, some manufacturers do that. NXP for example. I don't like it; I always have all three pads, and all three leads, in a straight line. I've seen a few cases where a transistor with staggered legs gets bumped and the middle lead gets crumpled or weakened, or pushes the whole pad off the board...
  19. KrisBlueNZ

    Modify circuit to add switch and timer

    Colin, this post helps no one at all. Please don't waste space and time posting useless comments like this.
  20. KrisBlueNZ

    Capacitive Reactance Circuit

    You might have turned it too far and damaged the LED with overcurrent. You need a resistor in series with the potentiometer to limit the current to the LED's maximum rated current. For example if it's rated for up to 50 mA and its forward voltage is 3V, that means the resistor must drop 2V at 50...
Top