“Cool Stuff”: ERI 788 Series All-Pass FM Analog/HD Radio Diplexer
One in a series about the
recipients of Radio World’s 2012 “Cool Stuff” Award.
ERI says its new high-level
diplexer does not have the high insertion loss associated with 10 dB hybrid
injectors, thus it’s more efficient with analog and digital power. The system
gives an FM station that is operating a –20 dBc digital signal with a 10 dB
hybrid injector the opportunity to increase digital power without having to
invest in a new transmitter.
The diplexer is rated for up to 30 kW analog and 5 kW digital input
power. All-pass analog insertion loss is –0.35 dB or less, digital loss is –1.4
dB. Group delay performance is better than other high-level combining methods,
ERI says, and is “readily correctable by currently available FM transmitters.”
Group delay of the analog signal is less than 350 nanoseconds; digital delay is
less than 600 ns. A typical package, including field setup, goes for about
ERI’s Bill Harland,
left, accepts congrats from Radio World’s Paul McLane.