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LXT/R

LXT/R

One Line Encoder/Decoder

Product Overview

The Basic LXT/R One Line Frequency Extender System works with a standard dial telephone line or a cellular telephone to pass 250 Hz of additional low frequencies. This results in more natural sounding audio and eliminates the “tinny” telephone sound. There are over 10,000 Comrex frequency extenders in use around the world. This is a well-proven technology that, unlike the newer POTS codecs, does not depend on modem connect speeds for performance.  Therefore, frequency extenders will work on lower-grade circuits.


The LXT/R combines the functions of older one line encoders and decoders. The LXT/R may be set up for sending or receiving by pushing a single switch. (An LXT/R is required at both the sending and the receiving ends of the telephone line.)

Since the LXT/R input and output operate in either balanced or unbalanced modes, it interfaces easily to a wide range of audio equipment. A high frequency enhancement circuit has been added to the encoder to provide improved audio quality. XLR connectors provide convenient audio hook up and a telephone coupler is built-in for easy, direct connection to the phone line. An optional rack adapter is available.

About One Line Frequency Extenders

Telephone lines sound tinny or thin because they only pass 300 Hz to 3100 Hz. Comrex One Line systems encode program audio by shifting all frequencies up by 250 Hz. Thus 50 Hz becomes 300 Hz and passes through the filters on the phone line. At the decode end, all frequencies are downshifted 250 Hz, restoring 2 1/2 octaves of program energy to the low end (at the expense of 1 /3 of an octave at the high end.) For voice material particularly, it is the lower frequencies between 50 Hz and 300 Hz that carry the resonance and natural sound of program audio.

Frequency Extender Applications

Frequency Extenders have a valuable place in any broadcaster's "remote kit." Here are a few common uses of the One Line system:

Sports Remotes

Listening to the restricted frequency response of telephone audio for any length of time can cause "listener ear fatigue." If any of your sports programs are broadcast on telephone lines, you should consider using a frequency extender to improve your audio quality.

Church Loops

Dedicated equalized circuits are often expensive or unavailable. An LXT/R installed at the church and fed by their PA system, and an LXT/R at your station will do the job at a modest cost. With the addition of an auto-answering coupler, the church can simply be dialed up and put on the air automatically.

Weather Feeds

Many weather services have one line frequency extender encoders. With an LXT/R at the receiving end, your weather reports can sound like they are coming from your studio rather than from out-of-state.

Ad-hoc Networks

In some cases, it is not practical to use a satellite for network delivery. The one line frequency extender has proved to be a cost-effective alternative for many types of program feeds, including state news, farm reports, regional business reports and sports.

Backup Audio

Whether you're going across town with an RPU or around the world on satellite, it's nice to have an insurance policy. Dial lines are available everywhere and they don't suffer from frequency overcrowding and fades ... or require any "technical" expertise.

LXT/R Specifications

Connections

  • TEL line: RJ-11C 6-Pin Modular Jack
  • TEL set: RJ-11C 6-Pin Modular Jack
  • Audio in: 3-pin XLR female
  • Audio out: 3-pin XLR male

Levels (Decode/Receive mode)

  • Input: -40/+8 dBm from telephone line externally adjustable
  • Output: 0 dBu
  • Active balanced or unbalanced.

Levels (Encode/Transmit mode)

  • Input: -20 to +8 dBu
  • Externally adjustable, active balanced or unbalanced Output: -9 dBm to telephone line

Power

  • External, Plug-mount supply 120 VAC/60 Hz or 240 VAC/50 Hz
    Specify when ordering.

Power requirements

  • +/- 12V @ 100mA

Size

  • 1.75” H x 9” W x 8” D
  • 4.4cm x 22.5cm x 20cm

Weight

  • 2 lbs 8 oz; 1.14 Kg

FCC Registration #

  • DXD6SN-13225-WP-N

Ringer Equivalence

  • 0.0B