Description
Wheatstone Corporation is now shipping its FM audio processors with new Wheatstone® baseband192 technology for direct AES/EBU output into any FM transmitter equipped with a digital baseband input, such as those from Nautel and BE.
Wheatstone® baseband192 uses open standard technology that eliminates the need for an analogue composite interface between processing and transmission — clearing the last obstacle to a 100% digital air chain.
“We simply digitize the entire multiplex spectrum up to and including the RDS, then send that digitized signal directly to the modulator of the exciter” explained Jeff Keith, senior Wheatstone product design engineer.
The baseband192 interface is now available as a standard feature in Wheatstone AirAura X3, FM-531HD and VP-8IP audio processors.
Unlike other approaches, baseband192 digitizes the entire multiplex spectrum including the RDS and SCAs up to 67 kHz for direct AES-EBU into the FM exciter. Unique to baseband192 is the ability to piggyback the RDS and SCA signals in digital form, eliminating the need to re-route these signals directly to the FM exciter instead of passing RDS and SCA signals through the processor (as is the practice without the digital multiplex interface). A single AES/EBU cable between the Wheatstone processor and the transmitter carries the baseband signal, bypassing the need for multiplexing in the exciter and eliminating the resulting signal overshoot and associated loudness tradeoff. Because the baseband192 signal encompasses the entire multiplex spectrum after stereo generation, it also includes any loudness increases that may have been contributed by the FM processor’s composite clipper.
