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  1. KrisBlueNZ

    Yamaha integrated receiver SR-300 subwoofer not working

    The service manual is available at http://elektrotanya.com/yamaha_ns-b380_ns-br300_ns-p705_sr-300.pdf/download.html Here's the subwoofer output circuitry. Click the image to enlarge it. It's based around IC303, a TAS5342LDDV (data sheet at...
  2. KrisBlueNZ

    Stage Line 500W amp repair project

    Farnell are based in the UK. But I think you have to open an account with them, and I don't know how reasonable their shipping costs are.
  3. KrisBlueNZ

    Stage Line 500W amp repair project

    According to the schematic they should both be 4.7Ω, 3W. When they were new, their colour bands would have been yellow, violet, gold, gold. They have both discoloured in slightly different ways. IMPORTANT! I forgot to mention this. These resistors must not be wirewound! Standard wirewound...
  4. KrisBlueNZ

    Do not feed the troll: vead

    Recently, hevans1944 and (*steve*) and I have been trying to help user "vead" understand the basics of the 8051 MCU core. To check his understanding of the basics, I explained how the core executed a particular instruction and asked him to give a similar explanation for a different instruction...
  5. KrisBlueNZ

    decoder for 8051

    VEAD. YOUR ENTIRE POST was COPIED WORD FOR WORD from http://renusblog.codemyne.net/Admin/Post.aspx?postid=7. YOU WILL NEVER LEARN ANYTHING IF YOU ONLY PRETEND TO UNDERSTAND. I am very tempted to ban you from Electronics Point immediately for plagiarism and outright lying, and as a...
  6. KrisBlueNZ

    Help indentify these components (IC, Capacitors etc)

    Yes, the 78L05 in an 8-pin package is the same as the 3-pin part with the extra pins just commoned up. That SOT-23 device marked W1P could be a transistor, a MOSFET, a single or dual diode, or possibly some other type of component. Transistor or MOSFET is most likely. I tried a few SMT marking...
  7. KrisBlueNZ

    Help indentify these components (IC, Capacitors etc)

    The first IC looks like a Fairchild 78L05 in a SOIC-8 package. See https://www.fairchildsemi.com/datasheets/LM/LM78L05A.pdf. The LM358A and LM358N have the same pinout. The A suffix indicates tighter specifications than the version without the A; the N suffix indicates a DIP-8 (through-hole)...
  8. KrisBlueNZ

    decoder for 8051

    1. Don't start another thread. 2. Do you understand post #68 in this thread? 3. Explain (like I did in post #68) how the 8051 core will process an instruction of 00010100. (Hint: look in the "dec" (decrement) instructions.)
  9. KrisBlueNZ

    hello guys

    Hi there and welcome to Electronics Point :-)
  10. KrisBlueNZ

    Can I drive a P-channel MOSFET from a 74HC138?

    OK, so your high-side switches are PNPs with their emitters at +5V and their bases driven from active-low 0V/+5V logic-level signals through resistors? That's fine. You should consider what will happen with a larger cube and/or a cube using different LEDs. Will 5V be enough? And how much...
  11. KrisBlueNZ

    differential amplifier

    Connect the positive supply rail to the positive power pin of the op-amp. (Often this is pin 7.) Connect the negative supply rail to the negative power pin of the op-amp. (Often this is pin 4.) The ground or 0V rail of the power supply becomes the 0V reference of the whole circuit. You should...
  12. KrisBlueNZ

    decoder for 8051

  13. KrisBlueNZ

    differential amplifier

    https://www.google.com/search?q=bipolar+power+supply&tbm=isch
  14. KrisBlueNZ

    Help finding inputs for micro display

    Hello and welcome to Electronics Point :-) It looks like there are at least 20 connections to it. I wouldn't assume that it accepts a composite video signal. Try Googling the part numbers of the large ICs on it. Don't expect to have any luck though; they're probably custom Sony devices.
  15. KrisBlueNZ

    Choosing an Opto Isolator

    If one of the tracks from the "contacts" (output) of the SSR to the solenoid went up in smoke, that's because too much current was flowing through it. That means that either the current was higher than it should have been, or the track was thinner than it should have been. Solenoids are...
  16. KrisBlueNZ

    Can I drive a P-channel MOSFET from a 74HC138?

    How have you connected your 64 high-side transistors? Do you have a schematic you could post?
  17. KrisBlueNZ

    decoder for 8051

    You just ignored my post. You are trying to teach yourself things that you don't understand. You are getting into details before you have even a basic understanding of opcodes and how they are executed. You will not learn from your own ideas. You will only learn by following the guidance of...
  18. KrisBlueNZ

    Can I drive a P-channel MOSFET from a 74HC138?

    Normally you would use a 74HC138 driving eight P-channel MOSFETs to switch the high side, to select one of eight planes of the cube. Each plane will have 64 cathodes, which would be driven by 64 low-side switches - standard transistors that are driven from shift register or latch ICs.
  19. KrisBlueNZ

    Trail Camera No Flash Troubleshooting

    Can you find technical information on your flash unit? For example, a service manual, or even just a schematic? How about uploading some photos of the inside of it, so we have some idea what you're talking about?
  20. KrisBlueNZ

    Trail Camera No Flash Troubleshooting

    The diode that measures short, does it measure short with one end lifted out of circuit? If it does, replace it. Simple, right? Don't start two separate threads on the same topic. I have merged this thread into your first one.
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