Digital Data, under construction


Heavy coupling on the transmitter ensures good low end frequency response, even with a lower impedance load. This is fine for Analog (audio) signals. Digital Data is a little different than analog data, or, voice for that matter. Digital information is made up of one's and zero's (1 and 0), with very quick transition from positive to negative wave form in the form of square waves. By over coupling the Tx line with a 100 uf cap will actually "distort" the square waveform. The recovered data at the Rx end will not show a good "eye" pattern and cause intermittent connection for the nodes. Therefore, use about a 4.7 uf cap instead. Some of the packet sites even use a 1uf cap. When available the pictures will illustrate the degradation over coupling does. For the receiver (detected) audio, the manual calls for a 4.7 uf cap, so we should be ok in that direction.



 

 

 

 

 

 

 





Additional information on:

  • Analog wave forms and distortion
  • Wires that carry data

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