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  1. kellys_eye

    Help with BLDC SENSORLESS motor control

    It takes a finite amount of time to deliver a conversion - it may be that even the slightest delay will affect speed. Try using the ADC in it's fastest conversion mode and see what difference it makes.
  2. kellys_eye

    What is a toggle switch?

    Never heard of Google?
  3. kellys_eye

    Help with BLDC SENSORLESS motor control

    What speed does your ADC work at - it probably isn't 'instantaneous'.
  4. kellys_eye

    Short pulse output

    It's called a one-shot (monostable) circuit. You can get the pulse output to start at button press or button release depending on what way you want to trigger it (rising edge or falling edge). Look at the datasheet for the HFC4047 (single monostable) or 4098 (dual monostable) or even the...
  5. kellys_eye

    Help me fix my subwoofer! Fuse keeps blowing - Tannoy TS12

    Disconnect the power supply DC output and retest with another fuse. If the fuse blows the PSU is faulty. If the fuse doesn't blow then the amplifier output stage is faulty.
  6. kellys_eye

    Working on a 3-voice 40106 oscillator. Need help...

    Not wrong there! Lovely stuff.
  7. kellys_eye

    The LM317 Adjustable Voltage Power Supply kit

    Not perfect but it will work. As above, expect 1.2 to 9V (ish) variable output from that input. Laptop PSU's are '10-a-penny' these days - lots of them are junked because the cable at the DC plug end often breaks internally, rendering it useless for the laptop but ideal for other purposes...
  8. kellys_eye

    music amplifier with just resistors (falstad simulation.)

    Yeah - in the same way climate simulations say the planets doomed...... it ain't - and your real world observation will prove just that, just as it does for the climate b0ll0x.
  9. kellys_eye

    music amplifier with just resistors (falstad simulation.)

    What the *** are you talking about?
  10. kellys_eye

    Working on a 3-voice 40106 oscillator. Need help...

    Logic IC's will only have two states - logic 0 and logic 1. In standard TTL logic this will be 0V (near enough) and 5V (near enough) respectively. In CMOS circuits it will be 0V and whatever the supply rail voltage is. In other words there is no difference in level (amplitude) regardless of...
  11. kellys_eye

    Director of Rodent Mitigation

    IS that 'Demorat' or real rats - I sometimes fail to make the distinction.....
  12. kellys_eye

    LM4876MX audio amplifier oscillation problem

    What kind of construction method (layout) are you using? If trying to deliberately amplify signals in the 'few hundred kHz region you will need some pretty good 'screening' in terms of track layout etc.
  13. kellys_eye

    Looking for a specific light-activated switch (12V DC)

    Put double-sided sticky tape on everyone else's cradle.....
  14. kellys_eye

    The LM317 Adjustable Voltage Power Supply kit

    Just an observation - the transformer appears to be labelled as a 220V AC input, 12V AC output. If built/used in the UK it (the transformer/rectifier part) will have around a 15V DC output feeding the LM317 and, with the internal volt-drop requirement of the LM317, would give an (approximate)...
  15. kellys_eye

    Automatic current/voltage regulator for LEDs

    What if the LED fails open-circuit? What happens if an LED fails short-circuit? The plain old LM317 can be configured as a constant current regulator (see the datasheet) as well as a constant voltage regulator. You can wire them in series to get constant voltage AND constant current. Then...
  16. kellys_eye

    Tube Receiver Audio Matching Transformer

    Requires it for what?
  17. kellys_eye

    Add BlueTooth Audio Transmitter to Amplifier?

    Yes, but severely distorted unless you use an attenuator (volume control) on the speaker output - see post #2
  18. kellys_eye

    Sb390 equivalent replacement

    High speed rectifiers can be found very easily. The 1N4*** series are rated at 1A and the 1N54** at 3A and BOTH versions are available as UF(4 or 54)*** coding for the 'ultra-fast' versions. i.e. UF5402 = 100V @ 3A i.e. UF4007 = 1000V @ 1A etc
  19. kellys_eye

    Advice to up rate a circuit board power handling

    You could remove the existing relay and wire the coil connections to a standard 'car' replay (plug-in type) which itself would be able to handle more than enough current. Don't forget to include a fuse just to be safe.
  20. kellys_eye

    Help needed to build a Simple radio to generate a tone

    My understanding is that the driver/pit simply can't UNDERSTAND what's being said (with the noise I'm not surprised) but the tone is clear enough to state 'I didn't hear you'.
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