Shaping radio today and tomorrow

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Shaping radio today and tomorrow

Jul 1, 2002 12:00 PM, By Kari Taylor, associate editor

Do you remember?

Originally designed in 1975 and 1976, Pacific Recorders and Engineering touted the benefits of separating the functions of processing and limiting an audio signal. The Multimax AGC/processor boasted three-band processing with energy-based, open-loop compressors for the active gain control circuitry. A gated release circuit was used to smooth band tracking and gain control. Separate versions were sold for AM or FM use. These were mono units, so two were needed for stereo. Many TV stations installed FM units as well.

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The Multilimiter featured a gain-riding compressor, a variable compression ratio fast limiter and an ultra-fast peak control limiter to provide peak control without a clipper.

Manufactured from 1976 to 1981, PR&E records show that there were more than 1,650 FM Multimaxes, 1,400 FM Multilimiters, 760 AM Multimaxes and 700 AM Multilimiters sold.

That was then

The Drake-Chenault tape duplicating system installed in 1978.

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Drake-Chenault, one of the early automated programming providers, supplied more than 1,000 automation tapes each week to 300 stations through the 60s, 70s and 80s. A typical automated radio station could air tapes that were one week to one year old. It was important that all aspects of the production and duplication process were consistent. The production of music programming tapes for automated radio stations at Drake-Chenault evolved into a highly regimented process that produced a polished, consistent product week after week.

The first duplication system was built in 1975 with nine Crown SX-722 decks. One master playback deck fed all nine machines. Stereo or mono copies could be made.

In 1978, the Crown decks were replaced with 24 Technics RS1500-US decks (shown here), which had much better transports than the Crowns. The isolated loop tape path was highly stable with less than 20 degrees of phase shift at 15kHz. This system had two master playback decks. Any of the 24 slave recorders could produce a stereo or mono copy from either master playback deck. A master start button would initiate the command for all 24 decks to start at once, an event that would make the floor shake. The 25Hz automation cue tones were generated and injected into the copies during duplication.

Info from Hank Landsberg. More info is available

Sample and Hold
A look at the technology shaping radio

US Digital Radio Receiver Shipments Forecast
Source: In-Stat/MDR, 4/02

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