User Tools

Site Tools


podcast:ddop:public:episode_201909

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

podcast:ddop:public:episode_201909 [2019/08/10 03:17] (current)
mikewills created
Line 1: Line 1:
 +====== Episode 2019-09 - Modulation ======
 +Hello and welcome to the next edition of the Mike Wills Podcast! This is the Dog Days of Podcasting edition for {insert date here}. I am WX0MIK and my name is Mike Wills. This season, we are covering amateur (or ham) radio.
  
 +===== Notes =====
 +  * Modulation is what enables us to communicate information using radio signals.
 +  * Bandwidth
 +    * We now know that a frequency can have a strength and amplitude
 +    * Signals are actually spread over a range of frequencies. From less than 300 Hz to over 3000 Hz.
 +    * Most of the modes have pre-defined bandwidth and in fact, in some cases, the FCC dictates that bandwidth you can use.
 +  * Modulation
 +    * Adds information to the signal. ​
 +    * A signal without information is unmodulated
 +    * Can be analog or digital
 +    * Two types are AM and FM
 +  * Continuous Wave (CW) or Morse Code - This is the simplest form of modulation using dits and dahs.
 +  * Amplitude Modulation - varying the power and amplitude of a signal to add speech or data.
 +  * Single Side Band (SSB) - Take an AM signal and use only 1/2 of the signal. There is then an upper sideband (USB) and a lower sideband (LSB). ​
 +  * Frequency and Phase Modulation (FM and PM) - Mostly used interchangeably. ​
 +  * Bandwidth of Modulated Signals
 +    * SSB is low bandwidth and thus can travel much further. CW is even lower yet and thus better yet for long distances.
 +    * CW uses 150 Hz
 +    * SSB digital uses 500 to 3000 Hz
 +    * SSB voice uses 2 to 3 kHz
 +    * AM voice uses 6 kHz
 +    * AM broadcast uses 10 kHz
 +    * FM voice uses 15 to 15 kHz
 +    * FM broadcast uses 150 kHz
 +  * There are some variations and rule surround this, but generally this is that case. The book will explain when this changes.
 +
 +===== Wrap Up =====
 +Thank you for listening. 73 from WX0MIK.
 +
 +===== Contact Information =====
 +  * Twitter: https://​twitter.com/​mikewills
 +  * Facebook: https://​www.facebook.com/​mikewills
 +  * Email: <​[email protected]>​
 +  * Website: https://​mikewills.me
podcast/ddop/public/episode_201909.txt · Last modified: 2019/08/10 03:17 by mikewills