Information Station Specialists is the best known source of traveler's information stations, highway advisory radio, advisory signs and services needed to reach motorists. Learn more about Information Station Specialists.
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 HQ5.1 TM
Broadcast Quality Audio Processor
HQ5.1 TIS Audio Processor 
The HQ5.1 Broadcast Quality Audio Processor has been certified by the FCC to operate in tandem with the TR6000 (TIS/HAR) Transmitter to effect an increase in broadcast audio quality. The processor replaces the TR6000's audio filter and increases the audio bandwidth of the broadcast from 3000 to 5000 Hz, adding compression and limiting functions. The result is a brighter, louder and more intelligible reception that often can be monitored at a greater distance.

This professional audio processor that meets National Radio Systems Committee (NRSC) mandated transmission standards for AM broadcasting within the United States. Incorporates tight peak control, adaptive pre-emphasis and low-pass filtering. Meets new FCC audio filtering standards for expanded bandwidth Travelers Information Radio Stations (TIS). Certified by FCC on 2-18-2016 for exclusive use with the TR6000 Transmitter from Information Station Specialists.
"The new upgrade to our station has dramatically improved the strength and clarity of our signal. Thanks."

Kevin Valentine
Bernardsville, NJ, Police Department
"Just wanted to let you know I upgraded our transmitter with the HQ5.1 this week. Big improvement!"

Scott Currie
Auburn, WA, Emergency Management Department
"The new filter made a big improvement in signal quality."

Rob Jones
Salt Lake City, UT, Airports Department
"Gentlemen, the equipment sounds great!"

Emilio J. Gervasio
Standard Parking/O'Hare Airport
Processor Installation Processor Installation
Above, Chip and Chuck Freese of West Grove, PA, install the HQ5.1 Processor in their Information Radio Station, a process made easier because to their station’s dual-door cabinet design that allows access to the rear of the unit for convenient wiring 
Audio Comparisons
Sample 1 3K Standard
This compares to what a conventional
Travelers Information Station has sounded like until recently. The audio you are hearing is natural but is filtered through the 3000 Hz filter that these radio stations have been required to have in their transmitter circuitry until now.

Sample 2 3K Enhanced Audio
Here is the same transmitter broadcasting the same audio file that has been equalized brighter and limited. This is more what a more modern "file-based" station sounds like today. Better, but there’s still no audio above the 3000 Hz cutoff.
Sample 3 HQ5.1 Broadcast Quality Audio Processor
Now listen on the same automobile radio to that same natural audio file being broadcast by the same TR6000 Transmitter with the HQ5.1 Broadcast Quality Audio Processor added into the audio chain. Bandwidth is now 5000 Hz and the Processor is adding compression and preemphasis, too. The increased intelligibility and loudness of the resulting broadcast are evident.
  • The built-in peak controller can enhance or replace existing limiters. Ability to serve as an effective stand-alone processing system that can also be combined with pre-processing devices to create transmission signatures through a built-in peak controller.
  • Enhances signal intelligibility through adaptive pre-emphasis. A separate pre-emphasis protection limiter independently controls high frequency program energy for best use of the NRSC transmission characteristics. Feed-forward pulse-width-modulation techniques are used in limiter and adaptive pre-emphasis stages for colorless, quasi-digital control of the program signal.
  • Eliminates interference to adjacent channels via a sharp-cutoff, low-pass function. Active multiple low-pass filtering exceeds requirements for adjacent-channel protection, even under adverse conditions. An overshoot compensator eliminates any need for splatter-generating clippers to assure full modulation.
  • Frequency response (pre-emphasis defeated):

    ±1dB, 10Hz-4.85kHz
    “PROOF” mode: ±0.5dB, 10Hz-15kHz

  • Distortion: less than 0.2% THD, 10Hz-cutoff with peak limiter off. Less than 1% THD, 200Hz-cutoff with peak limiter on.
  • Noise: better than 75dB below full carrier modulation (assuming NRSC de-emphasis).
  • Fixed pre-emphasis: The US version follows the “truncated” 75µs curve specified by the NRSC transmission standard. Alternative versions employ pre-emphasis appropriate to the service and the cutoff frequency.
  • Input: active-balanced, bridging; accepts nominal program line levels between -15dBu and +15dBu.
  • Output: active-balanced, 600-ohm resistive sources; delivers 0dBm to +15dBm into 600 ohms.
  • Output: positive peak amplitude is continuously variable up to +100%.
  • Power requirement: 105-130VAC or 210-255VAC, 50/60Hz; 8W.
  • Size and weight: 1-3/4”H x 19”W x 7”D (1U); 7 lbs.
Quote Related Webpages
Bill Baker (phone 616.772.2300, extension 102) can provide a formal quote.