28-05-2017, 01:18 AM
I don't think I had ever quite grasped bandwidth, channels, resonancy curves and so on. It's funny but there's scope to expand from more practical engineering all the way into physics. I mean, the ARRL book is very in-depth but online the maths side goes much further (to the point I close the page).
Anyway, when you start out you get the basic explanation of the LO is set to 455 KHz plus signal at 7000 KHz to heterodyne an IF. Much of it I never fully understood, especially bandwidth. So, I advanced to a chapter just on am modulation and it's helpful. Modulation percentage was new to me and it states when a carrier is modulated, the peak amplitude power is the carrier power squared. There always seems to be stuff I don't know. Also I should add images always bugged me. Lawrence gave a great summary of image not long ago so bandwidth and side bands tie in with that.
Anyway, when you start out you get the basic explanation of the LO is set to 455 KHz plus signal at 7000 KHz to heterodyne an IF. Much of it I never fully understood, especially bandwidth. So, I advanced to a chapter just on am modulation and it's helpful. Modulation percentage was new to me and it states when a carrier is modulated, the peak amplitude power is the carrier power squared. There always seems to be stuff I don't know. Also I should add images always bugged me. Lawrence gave a great summary of image not long ago so bandwidth and side bands tie in with that.
