[DOC] [TLE] Vacuum tube - Wikipedia [PAR] In electronics, a vacuum tube, an electron tube, or just a tube (North America), or 
valve is a ... Not all electronic circuit valves/electron tubes are vacuum tubes (
evacuated); ... In the 1940s the invention of semiconductor devices made it 
possible to .... Little practical use was ever made of this property (however early 
radios... [DOC] [TLE] History of radio - Wikipedia [PAR] The early history of radio is the history of technology that produce and use radio 
instruments that use radio waves. Within the timeline of radio, many people 
contributed theory and inventions .... The next advancement was the vacuum 
tube detector, invented by ... It was durable, because it had no vacuum tubes to 
burn out. [DOC] [TLE] Telephone Transmission - Engineering and Technology History Wiki [PAR] May 2, 2015 ... Over the 125 years following the invention of the telephone, ... It was not just the 
higher cost of copper that inhibited its use, but more .... Vacuum-tube electronic 
frequency filters, devised by AT&T's George ... in 1927 over a long-wave radio 
circuit, connected to the conventional wired networks at both ends. [DOC] [TLE] Memories: A Personal History of Bell Telephone ... - Quello Center [PAR] Aug 6, 2015 ... to work there and contribute to its many inventions and discoveries. .... The Radio 
Corporation of America (RCA) had its .... 37, No. 1 (Winter 1987), pp. 73-80. The 
Future of AT&T Bell Labs and ..... Vacuum tubes were used in the oscilloscopes, 
which ...... The first transistor was a point-contact device (shown. [DOC] [TLE] What Does a Nobel Prize for Radio Astronomy Have to Do with Your ... [PAR] Apr 1, 1995 ... Has the spirit passed out of its Bell Labs, as some charge? ... scattered about are 
a pilot's helmet used for the first ground-to-air radio transmission ... inventors of 
the transistor; Clinton Davisson, who demonstrated the wave nature ... when the 
search for a solid-state device to replace the vacuum tube began. [DOC] [TLE] Dec. 23, 1947: Transistor Opens Door to Digital Future | WIRED [PAR] Dec 23, 2009 ... It's been called the most important invention of the 20th century. ... Vacuum tubes 
were bulky, unreliable and consumed too much power. So AT&T's research-and-
development arm, Bell Labs, started a project to find an ... Bardeen and Brattain 
demonstrated the transistor device to Bell Lab officials Dec. [DOC] [TLE] AT&T Archives : A Modern Aladdin's Lamp - AT&T Tech Channel [PAR] Dec 19, 2011 ... How vacuum tubes work, in animated sequences involving monkeys ... Watch for 
footage of ridiculously huge vacuum tubes that were used for radio transmissions
. ... a grid explain the three-element tube so clearly that a non-technical audience 
... (Formerly "Cyber Threat Report")  From the Labs  Science... [DOC] [TLE] Faraday to Shockley - Transistor History - Sites - Google [PAR] Charles Fritts used selenium to produce a low efficiency photovoltaic cell. ... and 
its first use by Fleming for the detection of radio frequencies in 1904. By the 
1920s the vacuum tube was king and the crystal detector was relegated for the .... 
with the expected results for a conventional semiconductor but silver sulphide 
less so. [DOC] [TLE] computer - History of computing | Britannica.com [PAR] Oct 19, 2016 ... But Schickard may not have been the true inventor of the calculator. ..... of the 
modern computer during the remarkable decades of the 1930s and '40s. ..... of 
the transistor, had demonstrated a devicea tube, called a delay line, ...... With 
their own computers in their labs, researchers began to use minis for... [DOC] [TLE] historical overview - Career Cornerstone Center [PAR] Although commonplace by the1880s, the telegraph had not yet lost its ... The real 
excitement, however, came from new electrical inventions, some of which had .... 
bulbs, motors, and a host of auxiliary devices all required a deeper ...... 
calculating machine that could be used for everything from vacuum tube

Question: In the '40s AT&T; used a radio with no conventional vacuum tubes to demonstrate this device invented in its lab
Answer: a transistor