Search results

Search Forums New Posts
  1. kellys_eye

    Pressure sensitive surface

    There are digitising pads that have pressure sensitive pens for drawing purposes. Monitoring the pressure on a pen tip seems reasonably achievable (ferrite core moving in/out a coil to alter inductance/frequency).
  2. kellys_eye

    Sherwood AM-7040 No Left Channel

  3. kellys_eye

    Need help, regarding LED circuit

    Pre-wired LEDs already have the series resistor fitted so no external resistors are required. Your eBay link shows the LEDs to be fully capable of working at 9V or 12V, running at 9V just means slightly lower light output. If you want to get the full brightness from them at 9V then you will...
  4. kellys_eye

    Sherwood AM-7040 No Left Channel

    The devices look like fully plastic bodies therefore no insulation is required but heat compound should be used (sparingly) to cope with surface irregularities. Of course, it doesn't help your cause that the pin outs differ.......!!!! Check the datasheets! Drain and Source are reversed on the...
  5. kellys_eye

    Need help, regarding LED circuit

    If the LEDs are rated for 12V operation then you ideally need a 12V supply. This presumes the LEDs are pre-wired with series resistors to ensure 20mA current flow when 12V is applied. At 9V they will draw 15mA and there will be a reduction in brilliance (not much) but they will still work...
  6. kellys_eye

    Piezo-charger

    I used the words volts and amps in quotes for a reason but thanks for clarifying that for the OP....
  7. kellys_eye

    Scratching noise on volume button

    WD40 isn't really a lubricant but I use Vaseline (petroleum jelly) successfully as it is grease-like and gives the control a lovely smooth motion after application. There is usually a gap between the body of the potentiometer and the material the track is mounted on (where the three pins exit...
  8. kellys_eye

    Please help to buy those components

    As per your schematic there are TWO windings so four wires. And as I mentioned, you MUST connect them with the correct 'phase' (i.e. the end of one connects to the start of the other). i.e. START - wind around 80-100 turns on the ferrite - END : START - wind two turns on the ferrite - END...
  9. kellys_eye

    Piezo-charger

    'Power' also known as 'energy'. The energy content of a piezo generated voltage is minuscule (tiny, negligible etc). Your test meter requires just μA to measure the voltage - it's simply not enough to do anything (useful) with.
  10. kellys_eye

    Morse code led without a micro controller

    Yes, as a former Radio Officer (merchant marine) the true SOS sound is ingrained in memory and discernible through any interference and at practically any (low) signal level. If the signal wasn't as you state it was quickly ignored (many Greek ships used to run their group callsign into one...
  11. kellys_eye

    Regarding Certification

    More important than the course, seek out a REPUTABLE learning centre to get the qualification from.
  12. kellys_eye

    Component

    Good find Harald - I was going to question the reverse of the board (the four pins at the top indicating something underneath) but well spotted!
  13. kellys_eye

    1960's Instrument amplifier identification

    Well the logo on the front panel is familiar but that piece of equipment looks to be early 70's and pre Vingtors move towards marine gear. It's lot older than the stuff I used to work with, that's for sure. I think you might get some success by contacting them directly for information - they...
  14. kellys_eye

    Finding a nano amp transistor for Solar LED Light Marker

    Somehow I doubt it......
  15. kellys_eye

    Finding a nano amp transistor for Solar LED Light Marker

    Why don't you just get some garden solar path lighters and fit an appropriate resistor to limit the LED current?
  16. kellys_eye

    Please help to buy those components

    Those inductors symbols are typical of the way they indicate the toroidal construction types. You can get tables of the various toroids and their parameters where the tables show how many turns of wire are needed to get a specific inductance. In your schematic, L1 is shown with two dots...
  17. kellys_eye

    1960's Instrument amplifier identification

    Vingtor are otherwise known as Vingtor-Stentofon and suppliers to the marine industry of communication and amplification devices. I used to fit their kit on new-build ships (oil tankers etc). Post a pic of the amplifier - it might ring a bell or two in my aged mind....
  18. kellys_eye

    1960's Instrument amplifier identification

    kinda answered your own question there I reckon!
  19. kellys_eye

    Repairing a slide potentiometer

    Given Paypal's security and credit card company bias towards the buyer I think that's a pretty poor decision making process. You won't fix it without replacing it.
  20. kellys_eye

    Morse code led without a micro controller

    I sympathize with your position. My own opinion used to be rather like yours in respect to processors and their 'take-over' of the simplest tasks although it has tempered somewhat over the years as I've grown to use and appreciate them better. But I also appreciate the thought processes that...
Top