When I started to work in the year of 1951 there were no such things like Electronics. We were all electricians and as such you had to repair, wire, appliances, motors and all other electrical installations. I also worked for years as a lift mechanic where I found Controllers that had DC relays which were cheaper to manufacture and were more quiet in operation. To obtain the DC current we used a selenium Plate full wave rectifier this gave us the DC to control the switches. We also used a small 4 plate rectifier as a blocking rectifier in some circuits to prevent a back feed.
Then came a thing called electronics, the first Fax machine was in the Army when someone told me he could send a picture of a map in Pretoria in a machine to the border and they could send a reply back. Now we have a Fax in our home. The 24 plate selenium rectifier was replaced by a 3 phase full wave block rectifier that could handle 30 Amps.
The blocking rectifier was replaced by a Diode. Relay controllers were reduced in size by the use of solid state switching. We carry our phone in our pocket and we are able to contact people all over the world from the comfort of our home. Because of electronics we have Computers, cell phones, and all the many other gadgets that we use from time to time. We were able to control AC motor speed by pole changing, 4 poles for fast speed and 24 poles for slow speed. Now with SCRs, we can control ac motors from full speed to stop. That is the road I was able to walk so I wish to have a hobby in the field of Electronics with the help of certain people who have unselfishly offered their expertise to old fogies like myself to respect and admire them for their efforts. Please keep up the good effort; you are always an example to people like me.
I must start to build a project or two to get the feel, as the saying goes.
(Stop and smell the roses)