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  1. KrisBlueNZ

    Carp fishing electronics

    Hi Peter and welcome to the Electronics Point forums :-) I'm interested in helping. Please post all the information you have on the receiver, the LED lighting unit, and the power source, and anything else relevant.
  2. KrisBlueNZ

    electronics revision help

    That's good! C1 is the first smoothing capacitor, and R1 and C2 are the extra R-C filter. R1 is not the load resistor, and it probably shouldn't be 1k. Can you delete the 1k marking on R1? You can add some information to the schematic. The transformer should probably be called T1, not T2. The...
  3. KrisBlueNZ

    electronics revision help

    Hi Tom, and welcome to Electronics Point. I have moved your question to the homework help forum. We don't give complete answers here. It's the old "teach a man to fish" thing. We encourage you to make an attempt, and we give suggestions and corrections. You need to make a start yourself. If...
  4. KrisBlueNZ

    ROM address question

    I've moved your thread to the "Homework Help" section. I think you're right; that question is referring to the reset and interrupt "vector" addresses, 0x0000 and 0x0008. They're not vectors; they're actually entrypoints. There is also a configuration word, which is supposedly mapped to program...
  5. KrisBlueNZ

    Designing a Time Delayed Relay

    That's a lot better. I would avoid the track from pin 6 on the top side. I can't see the copper on the bottom layer but I assume it duplicates the copper on the top. It's a number of years since I did any PCB layout so I'm pretty rusty on the details. I'm working on my own layout for the...
  6. KrisBlueNZ

    Designing a Time Delayed Relay

    No, no problem with structural issues. But you could reduce the vias to 40 thou or 35 thou. It depends on the manufacturer I guess. You just need to be sure the through-plating is good and solid.
  7. KrisBlueNZ

    Designing a Time Delayed Relay

    OK. If the Allegro circuit needs a higher current rating than the relay, then swap them round. I wouldn't do that. I would keep all the connectors different so there's no chance of confusion. Also I would stick with a known good quality brand. But of course it's up to you. It does affect the...
  8. KrisBlueNZ

    Could this FET be used to switch 12V/30A from a PIC

    If you use it with the source connected to 0V and the load connected between a +12V supply and the drain, it will switch 30A at 12V. But... (a) If the load is inductive, you must connect a diode rated for at least 30V across the load (with its cathode to the +12V rail) to suppress the back EMF...
  9. KrisBlueNZ

    Designing a Time Delayed Relay

    I suggest the Phoenix Combicon MSTB series. These are pretty widely used and there are several brands who make knock-off versions. The plugs have rising clamps so they won't mangle the wires. Here are some specific suggestions: For the AC input to the circuit...
  10. KrisBlueNZ

    Voltage-controlled switch

    You have failed. Yes. If you're developing a product for profit, and you require secrecy, I suggest you find someone who will sign an NDA, and pay them for their advice, rather than asking on a public forum.
  11. KrisBlueNZ

    ROM address question

    I'm not sure what they're referring to. The PIC uses the modified Harvard architecture, where the program memory and the data memory use separate address and data buses, so two different locations can actually be accessed simultaneously during normal program execution: the program memory where...
  12. KrisBlueNZ

    Designing a Time Delayed Relay

    OK, my suggestions re the layout. The paths from CN2 to the Allegro chip need to be THICK and should be duplicated on both sides. Also, when you get the board made, make sure it has plated-through holes. (That should be standard for double-sided boards.) For the connector pins, you will need...
  13. KrisBlueNZ

    Small Circuit needed for New Product Design - Help!

    On second thoughts, a larger device might be better for power saving. I don't have a problem with the device waking up around 100 times per second to update two output ports, but if it needs to poll the pushbuttons using the ADC each time, that will add a significant amount of load current. It...
  14. KrisBlueNZ

    Small Circuit needed for New Product Design - Help!

    I didn't actually recommend the PIC16LF1902; I just said that it's the smallest member of the PIC family that has an LCD driver. With the LCD you've chosen, you don't need any special hardware to drive it. The 1902 is an "enhanced mid-range" device, and it includes lots of stuff you don't need -...
  15. KrisBlueNZ

    electric pulse counter

    How many digits do you need? What power source do you have? Have you tried Googling electronic counter? I did and I got lots of hits. Have you searched on eBay?
  16. KrisBlueNZ

    Voltage-controlled switch

    Hi Richard and welcome to Electronics Point :-) Based on prior experience, I think you will get the most useful responses the most quickly if you give us a lot more information about your project. Your minimalist description leaves a lot of unknowns that we can only guess at, and this tends to...
  17. KrisBlueNZ

    Simple relay circuit help

    Oh! You're right. I must have thought the gold bands were brown. Sorry!
  18. KrisBlueNZ

    Simple relay circuit help

    Yes, 3k3 is 3.3k. Those resistors are 12k. Their colour bands are brown, red, orange, gold. That translates to 12k. 3k3 resistors will have colour bands orange, orange, red, gold. Or if they're less than about 15 years old, they will probably have five bands, which should be orange, orange...
  19. KrisBlueNZ

    Motion sensor lighting with a difference

    It would help if you could show a drawing of how you want this to fit together. I'm assuming that the sensor will be inside the bell of the lamp, pointing downwards, so when someone puts their hand under it, to either put something there or take it away, the sensor will detect this movement...
  20. KrisBlueNZ

    RCD Fault

    Yes they should. Maybe it was done by a "home handyman"?
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