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  1. KrisBlueNZ

    Delay timer circuit for a motor.

    OK that's my suggestion. It's based on a CD4093B CMOS quad NAND gate with Schmitt trigger inputs. Search this forum or Google for other mentions of the 4093 for a detailed description of what it does. This IC is represented by the four D-shaped symbols on the diagram. Its positive supply and 0V...
  2. KrisBlueNZ

    Finding the Right Caps for a Westinghouse Monitor

    Can you list out the Nichicons you fitted, including the alphabetic "series" code (the Nichicon equivalent of the "KF" or "GL" on the original caps)?
  3. KrisBlueNZ

    Mosfet selection for switching a solenoid

    Do you want an N-channel or P-channel MOSFET? What supplier? There's a very wide range of MOSFETs that will be suitable. Here's a list of suitable N-channel devices from Digi-Key in order of ascending price. The main difference between them is RDSon and manufacturer...
  4. KrisBlueNZ

    Increase output voltages from 4060B

    <insert Marge Simpson growl of frustration here>
  5. KrisBlueNZ

    Problem with Relay experiment (Make: Electronics #7)

    Hi there and welcome to Electronics Point :-) That's a very good problem description! It looks to me like you've done everything right. Is it possible your breadboard is damaged? Try moving the LEDs and the resistor, and the +12V feed to the common contact, over to the other side of the...
  6. KrisBlueNZ

    Is there such a boost converter?

    Hi there and welcome to Electronics Point :-) I can see two ways to do what you want. The first is to use an "inverting" converter, which generates a fixed voltage of the opposite polarity to the input voltage, and take the output across the combination of the input and output voltages...
  7. KrisBlueNZ

    Increase output voltages from 4060B

    As Adam said, the Qn output voltages on a 4060 should swing all the way between VDD (when high) and VSS (when low). If you're only getting 0.5V at the outputs when they're high, you must have something loading the outputs down. Show us a schematic.
  8. KrisBlueNZ

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

    The value isn't very critical. 8.2Ω would be fine. Or a 10Ω 4W or 5W fusile resistor. Or a combination of series or parallel resistors, as long as they're all fusible and all the same value, and their wattages add up to at least 2.5W.
  9. KrisBlueNZ

    Finding the Right Caps for a Westinghouse Monitor

    Fantastic Dan! But I wouldn't leave those electrolytics in it. They will overheat, leak, and fail. Here are replacements I recommend from the United Chemi-Con KY series. They are all specified somewhat better than the CapXon originals. 2x 220μF 25V KF: d=8; h=11.5; ps=3.5; rc=0.55A; Zmax=156mR...
  10. KrisBlueNZ

    Computer PSU failure - voltages low - damage sustained?

    What do you mean exactly? Are you saying that the rail voltages are still wrong with the new power supply?
  11. KrisBlueNZ

    Help identify transformer

    Open circuit primary on mains transformers is often due to a failed thermal fuse. I don't know whether toroidal transformers can be made with thermal fuses - I don't know where you would put one - and the Wanji web site doesn't have much information, but it's a possibility that might be worth...
  12. KrisBlueNZ

    How to balance the bridge?

    Yes that's what I get. You've done it an even simpler way than I suggested. It's just all about ratios.
  13. KrisBlueNZ

    Audio Triggered AC light controller

    Hi there and welcome to Electronics Point :) First, your module needs power. That version has been assembled with R13 made from two 10 kΩ resistors in parallel, giving a combined resistance of 5 kΩ, so it is designed to operate from 120VAC. The Phase side of this 120VAC supply must be connected...
  14. KrisBlueNZ

    Finding the Right Caps for a Westinghouse Monitor

    X1, X2, Y1 and Y2 capacitors are used in the mains input circuitry for filtering. Those capacitors are electrolytics on the output rails of the power supply. And CapXon is a well-known trouble brand. You should replace them with low impedance electrolytics by reputable Japanese manufacturers...
  15. KrisBlueNZ

    Anyone know 220nF (400VAC) 7.5mm lead pitch capacitor?

    It would help if you told us the capacitance and voltage rating you want! Also, why do you think you need a capacitor with 7.5 mm lead spacing? What is the problem with the ones you found? Are they too big? There are laws of physics that will determine the minimum size of an X2 or Y2 rated...
  16. KrisBlueNZ

    Lift 1 kg weight using wind power from a fan

    Why convert to DC and back? I don't understand. Surely all you need is a propeller on a shaft, with a cog and chain or a wheel and cord, to raise the weight? If you really want to convert to electricity and back, then as Gryd3 said, just power the motor from the generator. In either case, a...
  17. KrisBlueNZ

    Converted atx psu whistle

    The likely reason for the whistle is that the supply is running with such a small load that even at minimum duty cycle, the controller is skipping cycles. Under normal load, the controller drives the switch and main transformer at a fixed frequency, for example 80 kHz, and varies the duty cycle...
  18. KrisBlueNZ

    How to balance the bridge?

    OK, think about what "balancing the bridge" means. It means that there is no voltage across the meter, right? So the left and right hand sides of the bridge are both voltage dividers, supplied from the same source voltage, VS. The right hand side will divide VS by a fixed ratio, which can be...
  19. KrisBlueNZ

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

    Yes, the SR2010 has the same specs as the SR2100. That is, it's a Schottky diode, 2A current rating, 100V voltage rating. I don't know if it's a good idea to use a 2W fusible resistor. The designs in the LNK364 data sheet specify 2.5W and 3W parts. The 2W one you found is convenient, but if you...
  20. KrisBlueNZ

    Audio Amplifier problem

    You mean lmgtfy? It's been around for quite a while. I learnt about it from (*steve*). Good eh!
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