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  1. kellys_eye

    LCD Display (Basic)

    Have a look at LCD Smartie too - it's a software package designed to be used with a multitude of LCD displays. Free to use, loads of display choices. http://lcdsmartie.sourceforge.net/
  2. kellys_eye

    LCD Display (Basic)

    There are a lot of parameters to consider here: Text size - it has to be readable at distance Clarity - will it require to be backlit? Viewing angle? Digits - Number of characters/lines Power - how will it be powered? Your idea, as good as it sounds, would be something many retailers would...
  3. kellys_eye

    Please help identify this variable resistor

    This datasheet shows a potential replacement pot: http://www.farnell.com/datasheets/202015.pdf You can check all the relevant dimensions but I think it fits with all you show. Found on the Farnell site at around $1.20...
  4. kellys_eye

    Unspecified capacitor

    Looks like a capacitor from a flash gun.....
  5. kellys_eye

    Help with bridge rectifier

    If 8/9 is really 3.5V AC (it's marked as 'fil' usually meaning the filament of a thermionic valve) then it's too low to drive the 7805. Measure the other secondaries (15/16) and look for at least 6V AC, no more than 12V AC and you'll be ok for the 5V supply. As for the supply for the 20W...
  6. kellys_eye

    Please help identify this variable resistor

    The mounting is less important than the shape and size of the shaft the knob sits on. Any suitable 10k pot can be fitted and wires connected to solder to the board but if the collar and shaft shape/diameter aren't correct then you won't (possibly) get the control knob to refit. That shaft...
  7. kellys_eye

    Potmeter "a" logo identification

    Yes you were! Silly me didn't pay proper attention - d'oh....
  8. kellys_eye

    Potmeter "a" logo identification

    The 'A' designation usually indicates the 'law' of the potentiometer - in this case A usually means 'linear' (B usually Log). Whilst this is common practise it's by no means standard practise though and depends on where in the world you are. See below:
  9. kellys_eye

    Help with bridge rectifier

    Point 1 will be the common for the +/-21V and needs to be connected to point 2 for the circuit to work - whether you also join it to point 3 depends on whether the circuits have a common return line (usually do). Other than that, the circuit as you have drawn it is a workable version.
  10. kellys_eye

    I just thought I'd measure a few diodes V vs I

    TBH - no. I can't think of any application where such data may be useful <shrugs>. Maybe I'm missing something?
  11. kellys_eye

    Musical Instrument Amps damaged by power surge or drop

    Sounds like one of the output transistors has blown which would give you the symptoms you currently experience. Pictures and some voltage measurements (that we can suggest) should localise the fault and we can take it from there.
  12. kellys_eye

    12v bar graph help

    You should be able to keep the supply to the LM3914 at 12V and adjust the resistors so the voltage span you want to monitor is as required. This will prevent you needing the additional 5V circuitry - an added complication.
  13. kellys_eye

    Help with bridge rectifier

    Your schematic for the transformer doesn't match the drawing you made.... Measure the AC volts between 10-11 and betwween 10-12 on the transformer and report back. Measure the AC volts between 8-9 on the transformer and report back. As it stands, the GND at the junction of C1 and C2 should go...
  14. kellys_eye

    VCLFO debugging

    That power supply won't work. It is only a SINGLE RAIL supply (3-15V DC). You need a DUAL RAIL power supply that will provide "positive-gound-negative" supply lines. Get TWO AA battery holders (that take 8-cells) to provide two lots of 12V from a battery source. Connect the positive of one...
  15. kellys_eye

    VCLFO debugging

    Across 4 and 8 it should read 24V. Put your meter black lead on 0V (pin2 of U4 will do) and then measure pins 8 and 4 of the same chip using the red lead. Pin 8 should show +12V and pin 4 will show -12V. If not, get back to us. If you put your black lead on pin 4 and the red on pin 8 the...
  16. kellys_eye

    Treadmill Motor Controller Board issue

    I'm actually on the RIGHT side of the pond so if Waleo27 wants to post the board to me I'll have a look at it.
  17. kellys_eye

    Help with transformer for Lumenis Laser

    Got a picture? Are you measuring AC volts at the blk/red wires? Or have you got your meter on DC? The white leads are a thermal cutout and it should read a short-circuit (on ohms or continuity ranges) but only test this with the power OFF.
  18. kellys_eye

    Robin 5000 pat tester

    I've heard tell, but can't confirm, that the 5500 manual is as good as the 5000 and about all you'll find online: http://docs-europe.electrocomponents.com/webdocs/0191/0900766b80191262.pdf Give it a go and let us know if it's usable.....????
  19. kellys_eye

    Anyone fancy designing a schematic?

    There are some good tutorials and introductory videos on the LORA range of transceivers over on youtube.
  20. kellys_eye

    VCLFO debugging

    Not interested in what your power supply reads - your DATA shows pin 4 of U2, U4, U5 and U6 as well as pin 6 of U3 etc all reading -0.5V. They should all be -12V
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