Tesla made a long distant carrier signal from Manhattan to West Point
that held up in court and 15 patents used by Marconi even though
recorded by lawyers before Marconi sued for radio royalties as
indicated in this book:
http://www.amazon.com/Alternating-Application-Telegraphy-Telephony-Transmission/dp/1893817016
Nikola Tesla on His Work With Alternating Currents and Their Application
to Wireless Telegraphy, Telephony, and Transmission of Power:
An Extended Interview (Tesla Presents Series, Pt. 1) [Paperback]
That book has a lot of information in Tesla's own words.
No circuits though. People add things to the base circuit and
made their own patents on circuits.
The basis of his radio invention was his testimony about making a signal
in his lab in Manhattan and receiving it as he tested reception at
West Point, New York. So we know he had a transmitter and a
radio wave receiver. That would be the first carrier signal.
I am not that up on the radio patents but channel tuning was his
doing by way of tuned circuits. Still done today and with carrier
frequency. The carrier is modulated by voice and video with higher
frequency carriers. Digital TV has digital signals carried now.
I have seen diagrams posted on the net said to be by Tesla that
were computer digital circuit gates.
Its good to ask questions since I once asked who invented the radio
and my father said Tesla. This was by court decree knocking down
a Marconi request for royalties for using the radio in WWI (and
or WWII not sure) since the decree came down in 1943 after Tesla dies.
So the US owed no one for the use of ratio circuits. The Nazis of
course didn't care a hoot who invented their world wide communications
they just used them.
Tesla did not make weak signals as he said present day radio
communications needed amplified receivers of great magnitude.
This is still true today as he said in the testimony. Tesla used
radio to move the fine matter in waves in a physical manner
he said was loss less. Thus some people wonder if Tesla
created propulsion in space from high pressure waves.
Tesla researchers such as William Lyne say Tesla would have
used coded signals, perhaps as mentioned by Tesla, for signals
from communications to power.
ED: Of course in Colorado he sent a signal or determined a
lightning strike went around the world and came back.
I do recall his signals would not go around the world
but straight through the Earth. Thus moving the fine matter
in solids as well as air and space.