demo of using AM-SSB(upper sideband only) at 14.5Khz as an Assisted Listening System communication medium... a Raspberry PI AM-SSB Transmitter and a Rohde's AM Detector AM-SSB Receiver
[ Ссылка ]
RECRI KEYER SDR MODULES to create the AM-SSB TRANSMITTER module
[ Ссылка ]
evaluate AUDIO QUALITY and LIP SYNC timing with the speaker
LIVE VIDEO/audio FEED from here: [ Ссылка ]
TRANSMITTER SETUP
Raspberry PI receives the VIDEO's audio and converts it to 14.5Khz AM-SSB output via its usb sound card...the LINE OUTPUT of this sound card goes to a class D 30 watt audio amp's input...the output of the audio amp goes to a step down audio transformer that connects to a 40 foot long horizontal perimeter wire loop antenna attached to the ceiling of the room where the Rohde's AM Detector circuit receiver is located...an audio cable from the Rohde's AM Detector circuit receiver's AM demodulated audio output is connected to the recording laptop's mic jack input and then into the screen recorder's audio input
RECEIVER SETUP
the Rohde's AM Detector circuit has a ferrite rod loopstick antenna attached to its INPUT PORT output port has an audio cable running to the laptop
NOTE: this AM Detector testing room has a very high ambient EMF field from multiple computers, radios, power supplies and printers... so there is some residual audio artifacts that make it through into the final audio output
for more info on building your own assisted listening system, please see the playlist here:
[ Ссылка ]
