=====ETA313-03: Theory lesson 2: Electric Circuits=====

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**Recommended reading: KonCEPT page 84-144 (chapter 3)**

Draw a superheterodyne TRX on the black board. Including antennas and propagation. 

Explain from TX to RX
  * DAC which stands for Digital to Analog converter. 
    * Audio BW: 300-3000 Hz
  * Pulse shape filter (LP)
    * Show other filter symbols
  * Mixer -> BP filter
  * Oscillator
  * Amplifier
  * Mixer -> BP filter
  * Oscillator + Frequency multiplier
  * Power amplifier (PA)
  * Antenna


  * Antenna
  * Low noise amplifier
  * The rest of the superheterodyne receiver 
  * ADC which stands for Analog to Digital converter

Explain what is heterodyne/homodyne

Direct converting (DDS) radio and direct sampling. 

Dictionary

^ English ^Svenska ^ Comment ^
| Bandwidth             | Bandbredd               | | 
| Transmitter           | Sändare                 | | 
| Receiver              | Mottagare               | | 
| Transciever           | Sändtagare              | | 
| Mixer                 | Blandare                | | 
| Amplifier             | Förstärkare             | | 
| Power Amplifier       | Effektförstärkare       | | 
| Low-noise Amplifier   | Lågbrusförstärkare      | |