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  1. kellys_eye

    Can I create and inexpensive wearable proximity warning device for the visually impaired?

    ahhh... that helps. This is school-grade stuff then? Look into a standard PIR detector device (your bog-standard yard light - in particular the sensor) and experiment with the sensor/filter/reflector to give the kind of coverage/detection range you want. This will only work for IR-radiative...
  2. kellys_eye

    What type of voltage regulators to use for IoT

    If you have specific details for the medical device (or whatever) you want to use then of course a separate PSU can be used to suit its needs but overall your need for supplies with μV ripple is 'ridiculously' over-rated. Find the specifications for the active devices being (or planned to be)...
  3. kellys_eye

    What type of voltage regulators to use for IoT

    Ask 'why' you need to reduce ripple to μV range and consider 'should you'? Unless you're going down the scientific/medical route there is (probably) no requirement to be so specific with such factors. You're talking 'home automation' and tens of thousands of people do it using the methods you...
  4. kellys_eye

    Power supply help?

    which means the main board has an 'issue'. Try an alternative PSU (use an old computer PSU if you have one) and see if it still happens. Otherwise post a close up, in-focus, image of the main board so we can look for potential problems.
  5. kellys_eye

    Can I create and inexpensive wearable proximity warning device for the visually impaired?

    This is one of those 'I want to make a s**t load of money but need 'your' knowledge to do it' threads. Compare the OP's 'parts list' to Hop's description and note the vast gulf between them - and 'we're' supposed to fill in the gaps????
  6. kellys_eye

    I don't understand the meaning/relevance of output impedance.

    Look up maximum power transfer theory. Basically the source and load must MATCH to attain max power transfer.
  7. kellys_eye

    Can I create and inexpensive wearable proximity warning device for the visually impaired?

    What do your components actually DO? How do they determine/detect proximity? Proximity to what? If it is to be wearable, how do you presume to power it?
  8. kellys_eye

    What type of voltage regulators to use for IoT

    Buck converters would work in all applications. There are techniques to minimise ripple where this is a potential issue.
  9. kellys_eye

    Motor controller ic

    Yes it does. Page 7 shows a schematic that illustrates the function of the device in a typical DVD application. How it might be controlled by software is impossible to say as this is 'per customer requirement'.
  10. kellys_eye

    How to increase the power output of a 300 w broadcast amplifier ?

    The schematic shown uses two anti-phase signals (via Q1 and Q2) that are 'added' through the 'combiner L10/L11. You can take the output of two complete amplifiers and combine them (again in anti-phase) to boost the power - this is a common method to build high-output power stages but requires...
  11. kellys_eye

    Changing out Electrolytic Caps for Polymer Ones

    Circuit boards and components in the motor industry usually have to comply with certain specifications, some of which are higher than found in commercial/domestic stuff - specifically temperature ranges. Capacitors used in SMPS circuits (on the 'smoothed side') have a tendency to fail more...
  12. kellys_eye

    I need good free schematics sites please

    You need to be more specific. If you have a make/model then Google may return the data you need. Failing that you could ask for a particular schematic on here but if you a desperate for one then you may end up having to pay (like the rest of us). Weigh up the cost effectiveness - a few £ on a...
  13. kellys_eye

    I need good free schematics sites please

    Google
  14. kellys_eye

    Parental control code

    Dang - having to agree to advertising before being able to view the link really grinds my gears. Most codes are simle 0000, 1234, 1111 etc but going through the 'reset' procedure usually allows you to change it anyway.
  15. kellys_eye

    Repair Vintage DC Power Supply, Sorensen DCR-B series 2700-Watt 600-4.5B

    Relevant links are allowed and this site can support pdf uploads and/or images as required. Post a schematic for the best response to your queries.
  16. kellys_eye

    Timer for laundry machine

    Isn't this a KISS project? The mechanicals are, why can't the 'electronics' be? The good-old motorised microswitch/cam system worked very well for decades, don't require 'soft switches', PSU's, semiconductors, LEDs etc. Servicing would be simple. There are many mechanically operated timer...
  17. kellys_eye

    Projector color wheel wiring

    Potentially a 4-wire stepper too. Can you measure the resistance between each connection?
  18. kellys_eye

    HT echoing too much

    Yes - any change in physical properties of a room will affect the acoustics but quite subtly to most ears. Depends on how MUCH change there has been. The curve of the bay may also deliver a 'focal point' to the sound.
  19. kellys_eye

    RGB Laser Power Board Issue

    Measure the current to the LEDs - DC clamp ammeter would be easiest but whatever you have that can do it will suffice. Note that there can be 10A+ (20A? 30A?) so make sure your meter is up to it. Use the working Red LED as a convenient comparison. You said you'd put the Red LED on the Blue...
  20. kellys_eye

    RGB Laser Power Board Issue

    No, they dont deteriorate when unused. Voltage can't 'disappear' without going somewhere. If there was a fault (as such) the fuse would blow. Since the voltage I just dropping it's indicative of a poor connection i.e the relay contacts.
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