I ask this because I swear, as a kid, I’ve seen a cameramen open up a telecom/telephone box and connect something to it. I assumed it was for an uplink back to the station to transmit video.
I ask this because I swear, as a kid, I’ve seen a cameramen open up a telecom/telephone box and connect something to it. I assumed it was for an uplink back to the station to transmit video.
Since most transmitters were located outside of city limits, equalized telephone lines were used to send the sound from master control to the transmitter.
This was the most common and cheapest way to make the connection to the transmitter until the advent of inexpensive microwave equipment. And microwave links have a nasty habit of fading out during tropospheric inversions so they were actually not as reliable, over long distances, as a phone line with a backup phone line that took an alternate path. (first hand experience here. Ya I'm that old) :-)
Most people today have no idea how you transmit analogue audio faithfully and reliably over long distances, via wires. Telephone engineers figured it out over 100 years ago.
by the way the old bell system technical journals are a fun read and are generally available at places like archive.org
The response of a twisted pair was pretty good over 2 to 4 miles as I recall but for a audio grade (50Hz to 5000Hz) various techniques were used that at the simplest involved coils but there were also active equalizers available for long haul circuits and/or "hi-fi" requirements. Remember DSL lines were/are shipping 1..2Mhz carriers over those same old telco lines. :-)
Of course some old trunk lines used paper insulation. Really. Which meant noise went up ... when it rained.