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  1. KrisBlueNZ

    Help identifying a 5 band resistor

    That's good information there Adam! I Googled "white band means fusible" and others have mentioned it as well. One of them mentioned Panasonic and Yageo. Resistor colour codes should probably mention this! I think the appropriate replacement would be a 0.5W fusible resistor such as...
  2. KrisBlueNZ

    Delayed Circuit connection

    That's good advice there from Gryd3. This circuit may do what you want. It uses a 74HC4066 or CD4066 quad bilateral switch IC to make the connections across the required keys. Keyboard keys are scanned by the microcontroller in a grid pattern. The alternative would be for the...
  3. KrisBlueNZ

    Question on use of Python language

    1 school = 'Massachusetts Institute of Technology' 2 numVowels = 0 3 numCons = 0 4 5 for char in school: 6 if char == 'a' or char == 'e' or char == 'i' \ 7 or char == 'o' or char == 'u': 8 numVowels += 1 9 elif char == 'o' or char == 'M': 10 print...
  4. KrisBlueNZ

    Audio Amplifier problem

    Hi there and welcome to Electronics Point. You have some nasty oscillation happening there. Here are a few things to try. The components in the Zobel network aka Boucherot cell, R1 and C3, must be good quality. C3 should be a film capacitor, not ceramic. The decoupling capacitor, C1, must be...
  5. KrisBlueNZ

    Heathkit IP20 Power Supply

    Upload the PDF to a free file hosting site. http://www.google.com/search?q=free+file+hosting+sites or http://www.ebizmba.com/articles/file-sharing-websites
  6. KrisBlueNZ

    Looking for feedback on an electronics idea

    I'm the same, ADRT. Another advantage of doing repairs: it forces you to stay up-to-date with technology - manufacturing, display technology, interface standards, modern components, etc.
  7. KrisBlueNZ

    Heathkit IP20 Power Supply

    Don't worry, I haven't forgotten you! I'm trying to draw it out in a way that I can understand, so I can figure out the best way to handle the R23 problem. If you have, or can find, any other documentation on the IP-20, that would be very helpful. Yes, I agree with that. Yes it will, but I...
  8. KrisBlueNZ

    JX2 vs R1J, resistors, can't find replacement...

    Yeah that's it. Good luck!
  9. KrisBlueNZ

    JX2 vs R1J, resistors, can't find replacement...

    You mean the black blob next to the "R150" marking"? I don't know what that is. It looks like a bit of goop that leaked out of something! The output transistors will be the two three-terminal packages at the back, that were screwed onto the heatsink. Q106 and Q111. Q106 is marked TIP35C; I...
  10. KrisBlueNZ

    JX2 vs R1J, resistors, can't find replacement...

    Hi there and welcome to Electronics Point :-) Yes, the three terminal part you have contains two 0.1Ω resistors, probably wirewound, with ±5% tolerance (indicated by the "J"). They are joined at the centre terminal. It can be replaced with two separate 0.1Ω resistors with ±5% tolerance. I...
  11. KrisBlueNZ

    Question on use of Python language

    Yes the forum software limits whitespace to two spaces whenever you paste text. You have to manually fix the indentation after you've pasted it. It's a total pain. Even if you paste it inside a CODE block, the whitespace stripping behaviour is the same. With the code indented as you have in...
  12. KrisBlueNZ

    Wiring a 7-segment display to a rotary switch

    Hi Luke and welcome to Electronics Point :-) See also https://www.electronicspoint.com/resources/got-a-question-about-driving-leds.5/
  13. KrisBlueNZ

    Looking for feedback on an electronics idea

    It might be better to start a contract repair service as a subcategory of some general "services offered" web site - something like freelancer.com but maybe more regional. Rather than trying to get a new web site off the ground, that is. Edit: And I agree with the other concerns raised - what...
  14. KrisBlueNZ

    Changing strobe pattern?

    Yes, that's the idea. You need to ground pins 8 and 9 of the TC4467/8/9, and pin 10 isn't used. Why did you choose such a high value for R4? I would use something like 12Ω or 22Ω to limit the peak current to about 0.5~1A to protect the TC4467/8/9 but still switch the MOSFET quickly. Quick...
  15. KrisBlueNZ

    Looking for feedback on an electronics idea

    As long as you don't try to promote a commercial venture here, you should be OK. I repair stuff as a hobby. I did an apprenticeship at a repair company when I was younger and that put me off doing it for a job. And nowadays I don't think it's viable except as a hobby, unless you're working with...
  16. KrisBlueNZ

    Dehumidifer - Does not Power On. Faulty Power Supply Board.

    Hi there wills07417 Are you still interested in fixing this board? If so, have a look at the vertically mounted grey resistor RF1, between the fuse and the four diodes. What are the colour markings on it? Measure its resistance with your multimeter on the 200Ω range, and one probe to each end...
  17. KrisBlueNZ

    Changing strobe pattern?

    That's a good start. You need to change the MOSFET drive circuitry, and you will need some kind of current limiting for the LEDs, unless that is built into the LED bank. If it is, you shouldn't show the LED bank as an LED - show it as a black box, or as an array of LEDs with a current limiting...
  18. KrisBlueNZ

    How to deal with someone

    I know you are not a bad person. You copied some text from a web site and posted it as your own work. You pretended that you were explaining something different from what I had asked you to explain, so you could use someone else's explanation, to trick me into thinking that you understood...
  19. KrisBlueNZ

    Resistor identification

    Some or all of the extra 0.6Ω may be resistance in your meter leads and/or poor quality multimeter. What resistance do you measure if you short the leads together? Subtract that from the 1.6Ω and you should get something closer to 1Ω.
  20. KrisBlueNZ

    Resistor identification

    Yes I agree, they look like 1Ω resistors, probably rated at around 2W. Have you measured them?
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