Hello

V4.31 and W7 Pro 64bit. Still being asked to check when I just logged on!

David

This is very simple, and merely consists of putting sufficient base current into the transistor, which will cause the transistor to switch between cut off and saturation. The detail depends on exactly what you are using the switch for. I would recommend that you get a good book on electronics and pe...

The essence of this is to have a 555 astable, which would supply a pulse to drive the display via an integrator to give you the appropriate speed of movement over the scale. Sound activation is a bit more tricky, but is from mic to amplifier to integrator and so on. Do you want a mechanical meter wi...

The motor spec shows 220 mA without load, and 660mA at max efficiency. 3V is presumably the max supply to the motor, so the remaining 3V is dropped over the resistor and the Vce of the transistor (usually about 0.2V). With 2.8V dropped across the resistor carrying 660 mA, the dissipation is near eno...

Yes, with the correct series resistor you could run the LEDs from virtually any voltage

On to the next stage. Have you got a circuit diagram? That will be the most useful thing. If so, concentrate on the area around the drum and the potentiometer, and see if you can track the signal through the circuit with the scope until the signal fails. If you can do this, the number of components ...

I am being asked to check with updates, although I have already done so!

Temperature controllers is a very wide subject, and your post does not really give enough information for the replies to be particularly specific. As a general rule, Google is your first port of call if you want to buy one ready made.

The important thing with LEDs of any description is not to exceed the current rating - the supply voltage is not really critical as a series resistor is all that is needed to control the current through the LED. The 30 mA rating you quote will be the continuous figure, and the 100 mA is a pulse rati...

Hello. This could be quite a simple problem - you say that you are building it from a kit, and that most of the drum synth and the potentiometer itself work. Try checking that all components are soldered neatly onto the board, and that there are no solder bridges between tracks. Check that all diode...