![Aircraft radio telephony transmitter, complete with round valve and microphone, 1915 | Science Museum Group Collection Aircraft radio telephony transmitter, complete with round valve and microphone, 1915 | Science Museum Group Collection](https://coimages.sciencemuseumgroup.org.uk/images/263/820/medium_1935_0618__0001_.jpg)
Aircraft radio telephony transmitter, complete with round valve and microphone, 1915 | Science Museum Group Collection
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Walkie-talkie Kenwood Corporation Ultra high frequency Two-way radio Telephony, kenwood, china, business, mobile Phones png | PNGWing
![Slone Railways. SOURCE Of CURRENT - —GRouNo DIAGRAM OF RADIO-TELEPHONY RECEIVING ANTENNA OSCILLATOR MICRO-PHONE TRANSMITTER PILOT-LAMP DIAGRAM OF RADIO=TELEPHONY TRANSMITTING STATION -GROUND X TELEPHONE RECEIVER GRID BATTERY TELEPHONE CONDENSER STORAGE ... Slone Railways. SOURCE Of CURRENT - —GRouNo DIAGRAM OF RADIO-TELEPHONY RECEIVING ANTENNA OSCILLATOR MICRO-PHONE TRANSMITTER PILOT-LAMP DIAGRAM OF RADIO=TELEPHONY TRANSMITTING STATION -GROUND X TELEPHONE RECEIVER GRID BATTERY TELEPHONE CONDENSER STORAGE ...](https://c8.alamy.com/comp/2ABY2ER/slone-railways-source-of-current-grouno-diagram-of-radio-telephony-receiving-antenna-oscillator-micro-phone-transmitter-pilot-lamp-diagram-of-radio=telephony-transmitting-station-ground-x-telephone-receiver-grid-battery-telephone-condenser-storage-battery-for-lamp-scientific-american-1907-09-28-2ABY2ER.jpg)
Slone Railways. SOURCE Of CURRENT - —GRouNo DIAGRAM OF RADIO-TELEPHONY RECEIVING ANTENNA OSCILLATOR MICRO-PHONE TRANSMITTER PILOT-LAMP DIAGRAM OF RADIO=TELEPHONY TRANSMITTING STATION -GROUND X TELEPHONE RECEIVER GRID BATTERY TELEPHONE CONDENSER STORAGE ...
![Round transmitter valve type T31 for aircraft radio telephony transmitter | Science Museum Group Collection Round transmitter valve type T31 for aircraft radio telephony transmitter | Science Museum Group Collection](https://coimages.sciencemuseumgroup.org.uk/images/276/225/medium_1935_0618__0002_.jpg)