Lets talk PWM controllers.

[melmerby]

44 minutes ago, Miss Prism said:

Looks like the Practical Wireless circuit vintage 1972.

 

That's the one.

My first version used lockfit transistors (remember them?) on veroboard.

I've still got one on a home etched PCB.

 

I added the acceleration/deceleration add-on to some of them

[JimRead]

On 11/03/2024 at 18:18, melmerby said:

How about this.

Bear in mind that a low frequency, full voltage, minimum pulse width circuit will rapidly knacker the brushes.

Hello Keith,

 

Errrrrr well here's a link to a motor that did 12 years at shows slowly shunting on micro layouts

https://ogaugemicro.blogspot.com/p/controllers.html

Please scroll down the page a bit to see the motor stripped down the brushes are worn down but hardly what you'd call rapidly.

 

Do bear this in mind as well:

Pulse controllers do heat motors but then so do ramping DC and DCC ones, the nature of the pickup from brush to commutator, from rail to wheel and from wheel to pickup is never a smooth exchange of power.

 

Cheers - Jim