Old School Light Chaser part 2

As promised, some more details of the construction.  Above is the circuit diagram, repeated from the last post.  The area highlighted in grey is one LED segment, construction of which is detailed below.


First, the base-emitter resistor and diode are wrapped together like this.

Then they're soldered together and the resistor leads bent into loops like this.

Then the pair of them are soldered to the base & emitter of the transistor.

 A second sub-assembly comprising the capacitor and LED is assembled like this

 Then the two sub-assemblies are combined like this.  Note that the capacitor & LED have been turned over since the previous photo.

Then the LED resistor and capacitor resistor are added like this.








Then exposed parts are covered in heat-shrink sleeving to prevent accidental short circuits, leaving only the ends of the leads exposed.


When enough of these have been made, they can be connected together and covered with more heat-shrink sleeving.  The first one in the string has a push-to-make button switch connected across the transistor's collector and emitter, and the output of the last LED segment is looped back to the input of the first.  The finished segments are about the same size as traditional Christmas tree lights, which is what I've been using them for.