Tieline Technologies



Thousands of customers around the world use Tieline's low-cost, affordable POTS/PSTN solutions every single day.

Tieline has been the market-leader in Plain Old Telephone Service (POTS/PSTN) broadcasting technology for many years, and Tieline codecs continue to provide ultra-stable, rock-solid connections over analog POTS lines.

Tieline POTS solutions provide 15kHz FM quality audio to broadcasters for just the cost of a regular phone call. In fact, it sounds so good your listeners will find it difficult to tell the difference between POTS and either IP or ISDN connections!

How can I use Tieline POTS...

Whether dialing over standard telco POTS lines or analog leased lines, Tieline POTS can be used for remote broadcasts (OBs), for inter-studio audio contribution, or even as a backup for studio-to-transmitter links. It is the ideal low-cost standalone solution or backup for higher bandwidth IP, ISDN, 3G or X.21 connections.

What connection options are available?

Tieline prides itself on being compatible with all major brands of codecs over five different network types - IP, 3GIP, POTS, ISDN, and X.21. We are fully compatible over POTS with Comrex Matrix, Access, Vector and Blue codecs.

All Tieline codecs include the following default profiles, which can be modified and saved as custom profiles using ToolBox software.

FM Quality Mono Program

Send bidirectional mono program audio of up to 15 kHz between two codecs over a single analog phone line using a single POTS plug-in module.

POTS Solutions single OB line

Bidirectional Mono Program Connection


FM Quality Stereo

Send bidirectional stereo audio of up to 15 kHz using two phone lines and two POTS plug-in modules in each codec.

POTS Solutions Stereo

Bidirectional Stereo Program Connection


FM Quality Mono with IFB

Send bidirectional mono program audio of up to 15kHz between two codecs and simultaneously provide full duplex off-air communications using two phone lines and two POTS modules in each codec.

POTS Solutions Mono IFB

Bidirectional Mono Program Connection with IFB


FM Quality Dual Mono

Using dual mono you can send two channels of audio from the same codec to two different destinations, or use a single codec to receive signals from two different remote codec connections. For example:

  • Send the same signal to two different codec destinations.
  • Send the same signal over two different connection transports, e.g. POTS and ISDN, as backup in case of a connection failure.
  • Send two different mono feeds to the same codec, or to two different codec destinations (using a custom dual-dial profile with differently programmed mono program splits).
  • Receive two different codec program feeds from two separate remote codecs, reducing infrastructure costs by purchasing 3 codecs instead of 4.

POTS Solutions Dual Mono Program

 Dual Mono Program from the Remote Site

POTS Solutions Dual Mono Program alternative B

 Dual Mono Program from the Studio


High Quality Bonded Mono Connections

Select the ManDflt MonoPgm  profile in a codec and if the codec detects two connections being dialed they will automatically be bonded to increase connection bandwidth. If a reliable 48kbps bonded POTS connection is achieved, the codec can use the Tieline MusicPLUS algorithm to send 20kHz quality audio.

You can even make regular voice Calls...

Tieline POTS G3 modules can be used to make regular voice calls, which is lets you:

  • Make a standard voice call from a Tieline codec.
  • Integrate a voice call into program content.
  • Dial into a hybrid telephone from a Tieline codec.

This is a great feature that lets you integrate a voice call into a broadcast, or you may simply want to make a voice phone call for communications

 POTS Solutions POTS voice

Integrating a POTS/PSTN Voice Call into a Broadcast


POTS G3 modules provide even greater stability than ever before...

All Tieline POTS modules create rock-solid connections because they measure the amount of fluctuation in line quality before working out the optimal bit-rate setting to connect at. Tieline's latest POTS G3 module includes more great features that provide more reliable and intuitive POTS connections than ever before.

Tieline's Smart DAA technology means modules correctly interface with local phone line characteristics in a large number of supported countries. Tieline POTS G3 technology also detects and filters ADSL and DSL signals and negotiates stable bit-rates on shared lines, as well as providing more stable bonded connections.

Discover the Tieline Difference today...

Thousands of customers around the world have discovered the Tieline difference as they confidently connect and broadcast crystal-clear audio, over POTS and a variety of connection transports, each and every day. Test drive a Tieline codec today and discover the Tieline difference for yourself...


  • Live, bidirectional FM quality audio over a single analog POTS/PSTN phone line;
  • Bonding of two POTS/PSTN lines for higher quality connections;
  • Stereo, dual mono and mono/IFB capability over two POTS/PSTN lines;
  • POTS module voice call capability for integration of telephone hybrids and talkback callers into program audio;
  • Low bit-rate, low-delay, high quality Voice G3* and Tieline Music algorithms for broadcasting voice, music and full duplex communications live and in real-time;
  • Smart DAA technology that automatically configures a codec for a country's line conditions and filters ADSL/DSL signals when using high quality line filters;
  • Ultra-stable and rock-solid connections with real-time line quality displays of local and remote codec connections;
  • Simple connection wizards for programming new POTS connections;
  • Profiles for programming different dialing configurations at different locations;
  • Store up to 80 numbers in the codec phone book.
  • One touch automatic dialing with one-touch automatic redialing or automatic reconnect functions;
  • Programmable automatic or manual call answering;
  • Automatic failover to a standby connection;
  • Full remote control of connected codecs from the studio.
  • A fully featured digital matrix router for routing inputs to your choice of digital and analog outputs.
  • Relay inputs and outputs for flexible machine control.

* From the 31st March 2011 Tieline has discontinued support for the Voice G3 algorithm. As a result it has been omitted from the v.1.6.72 firmware release and all codecs purchased after this date. Codecs with firmware v.1.6.72 or higher can connect to G3 codecs running older firmware versions, but will have to use an algorithm other than Voice G3. Voice G3 is usually used for low-bitrate connections over GSM and POTS. We recommend using Tieline Music as a substitute for these low bit-rate connections.