Search results

  1. Minder

    How do get Arduino to read the angular speed of a rotating shaft?

    Tachometer by definition usually functions as a rpm or shaft rotation rate, for position and direction control either a Quadrature encoder (2 pulses 90° apart), or a absolute encoder is used. The link by Martin is an explanation of the Quadrature type. M.
  2. Minder

    Transistor bias configuration

    I assume being of UK origin you are familiar with Monty Python? The post was an attempt at levity and a response to a previous comment.?:confused: M. .
  3. Minder

    4v motor damaged?

    If you are sure it is damaged beyond repair, it may be an opportunity to open it up and learn what technology it is? M.
  4. Minder

    Transistor bias configuration

    Now, I’ve noticed a tendency for this thread to get rather silly!:( (M.P)
  5. Minder

    Quick motor suggestions

    For precise positioning servo's generally require some kind of PID control, which includes a feedback device on the motor such as encoder etc. Non PID loop with say tach feedback is much less precise and usually used for rough point to point positioning using a limit switch etc and dynamic...
  6. Minder

    Quick motor suggestions

    I would have to dispute that statement, after working with AC,DC & BLDC servo motors for more that a few decades, the performance charts have typically shown maximum torque at zero rpm, and typically staying fairly flat or taper down slightly up to the max rpm. M.
  7. Minder

    24v Solenoid - AC vs DC

    If you have a linear type 24vdc supply right now, you could come direct off of the transformer secondary, you just need a blocking rectifier between it and the capacitor. Or simply a 240v/24v transformer. The resistance of an AC inductive device is very low, it requires the inductive reactance...
  8. Minder

    Good book for Electronics

    But see what happens when they disregard the normal universal standards for symbols, as they have done throughout the book. http://electronics.stackexchange.com/questions/67894/use-of-ground-symbols-in-circuit-diagrams At least in UK it is called 'Earth'. M.
  9. Minder

    Good book for Electronics

    At one time it was common to see a Pi filter in a power supply, this is a capacitor, series Inductor, and a second capacitor (forming Pi). Each has the effect of removing ripple. M.
  10. Minder

    Good book for Electronics

    With no load, the DC would be RMS x 1.414 (peak), any load will cause a certain % ripple, the percentage would be dependent on amount of load and value of capacitor. When using certain inductive devices, motors, relays etc, A capacitor is not often required with a full wave supply, as the...
  11. Minder

    Digital voltmeter - 500m cable

    Here is info on the sense lines I mentioned earlier. http://power-topics.blogspot.ca/2013/04/power-supply-remote-sense-mistakes-and.html M.
  12. Minder

    Digital voltmeter - 500m cable

    I don't see that it would for a high impedance meter? I would expect the current to be in the mA range or fraction of. M.
  13. Minder

    Transistor bias configuration

    Then of course there is a few types of transistors all having different characteristics, current bias to voltage bias. Bi-polar. Mosfet. BJT etc. M.
  14. Minder

    Digital voltmeter - 500m cable

    Usually the digital voltmeter has very high impedance, so there should be no problem with volt drop, I would use 20g shielded cable twisted pair. This is similar in function to the DC power supplies that have remote sense, except these adjust the source so that the destination voltage remains...
  15. Minder

    Total beginner... so I don't know if what I want to do is easy or hard!

    As pointed out, if you can identify the two windings you should be able to swap either 1 & 2 or 3 & 4. M.
  16. Minder

    Good book for Electronics

    AbeBooks clearing house is good source of cheaper hard copies. Usually world wide. M.
  17. Minder

    Total beginner... so I don't know if what I want to do is easy or hard!

    Yep, string the aerial along the clothes line.:p Galena has been attributed to the first semiconductor put to practical use in electronics. M.
  18. Minder

    Total beginner... so I don't know if what I want to do is easy or hard!

    My very first project as a young lad was a 'Cats Whisker' radio, Great, No batteries needed!!:cool: M.
  19. Minder

    Total beginner... so I don't know if what I want to do is easy or hard!

    That is almost back in the time when they were all known as 'Condensers':p M.
  20. Minder

    Total beginner... so I don't know if what I want to do is easy or hard!

    Partly right, the maximum rpm is governed by the load, no load is the condition where it can fly apart. It is common in machine tool spindles to decrease the field to obtain a little more top end rpm, but at the sacrifice of torque. In a shunt wound motor the maximum rpm depends on the field...
View older results
Top