Hi,
A friend showed me this circuit which is designed to operate a model rail points solenoid which typically has 4ohm coils for use at typically 12-24vdc.
Its also acts as a CDU allowing an initial current burst when the switch is changed over and then decays to almost 0 ma while it is held on.
Have built and tested the circuit and it does work, though needing a quiet high voltage to produce a good movement from the solenoid.
The problem is that cannot quiet see How the circuit actually works ?
A friend showed me this circuit which is designed to operate a model rail points solenoid which typically has 4ohm coils for use at typically 12-24vdc.
Its also acts as a CDU allowing an initial current burst when the switch is changed over and then decays to almost 0 ma while it is held on.
Have built and tested the circuit and it does work, though needing a quiet high voltage to produce a good movement from the solenoid.
The problem is that cannot quiet see How the circuit actually works ?