This page shows a complete transmission system incorporating a Band 1 Studio to Transmitter Link (STL). The link system enables the main transmitter and aerial to be placed on a remote high hilltop. Maximum range is then guaranteed because of the height advantage. The studio can be situated in a place more accessible for the staff. The link system used here is for band 1 frequencies which lie between 48 and 65 MHz. Signals at these frequencies can travel quite some distance, but the aerials are rather large due to the low frequency. Link systems are almost used universally by Private Radio stations and RSL (restricted service licence) stations. Larger outfits rely on high quality cable or fibre optic studio to transmitter links.
Although the now popular RDS generator is placed at the main broadcasting transmitter end, it could be placed between the stereo processor unit and the link transmitter. There is less chance of data corruption by placing the expensive RDS unit at the main transmitter, but...it could be stolen if the main tx site is unattended
One final point about link systems generally. The link receiver has to work alongside a powerful VHF main transmitter. It is absolutely essential that the link receiving aerial is tuned to the incoming link frequency and in the case of a dipole aerial, that a balun is fitted. Link aerials should always be horizontally polarised, whilst main output (88 - 108 MHz) are vertically polarised. If you 'coat hanger' the link receive aerial you can expect poor performance.