This Week:
*Amplifiers / Oscillators by VE3EJJ
*Transmission Techniques / Modes by VE3SUY
This week Ernie (VE3EJJ) covered a topic which was of great interest to me as a child: amplifiers. When I was young, I used to play with my CB radio, generally interfering with local CBers in Ottawa. I was always looking to get more performance out of my hand-held radio, so one day I found a company offering schematics to build a linear amplifier in the 26-28MHz range which covers the CB band. Of course, amplifying a license exempt band is prohibited, but I was a rebellious kid! I never did end up making the amplifier – the schematics were well beyond my abilities at the time (I was ~10y/o) but it was my first look at the topic.
The second topic of the night was the various modes of radio operation, starting with spark-gap and moving all the way along to a lesser known phase modulation technique. Bob (VE3SUY) gave an extremely helpful lecture which helps in understanding modulation methods such as AM and FM (amplitude and frequency modulation respectively). I was very familiar with the modulation methods as a result of plenty of self-study, however, it would have been a heck of a lot simpler to learn had I hear Bob’s talk sooner! The concept of block diagrams came up again, and it is worth mentioning that there are at least 5 questions in the Basic exam which test your knowledge of transmitter and receiver block diagrams. So it was an informative (theory heavy) night.
