De Belie Starstat 1800 Digital STL Link (Set ,antennas included)

This is the first license-free digital audio link that reaches a considerable distance (eg 33km). The link is license free in most European countries.

Official documents of the Netherlands’and Belgium’s spectrum authorities clearly state it works under a harmonized European standardard and can be used as fixed installed audio link under the PMSE directive. In the Netherlands, the link uses the frequency band 1785-1805 MHz 20mWerp. in Belgium and Europe: 1795-1800 MHz and 20mWeirp Without a clear line of sight 5km is easily achievable. With almost line of sight 15km. With full line of sight more than 33km is possible.

The price is in between a conventional analog set and 10GHz MPX STLs. STAT1800 accepts stereo audio via XLR inputs and converts these to digital Vorbis. A digital stream is created with forward error correction bits are added and where interleaving is applied. It is broadcast at 1.8GHz GFSK. The TX Octenna is an integral part of the transmission system and is connected by a low cost satellite 75 Ohm coaxial with the indoor unit (STAT1800).

The set output power is not affected by the coax loss as long as this loss is between 0 and 14dB. To achieve this, there is a power measurement system in the active antenna. The measurements are sent digitally over the coax to the indoor unit. A digital control loop in the indoor unit ensures that the transmission power is always equal to the desired power. The receiving system consists of the RX Octenna connected via a low cost satellite coax with the STAR1800 indoor unit. The coax loss should lie between 0 and 14dB. The RX Octenna includes a high gain passive antenna, bandpass filters and LNAs. This combination provides an extremely low noise figure. In the STAR1800 receiver further filtering and amplification takes place. The entire receiving system is designed as a large dynamic range receiver that is capable of receiving the smallest signal, even in the (frequency) vicinity of a strong signal in the same band. STAR1800 demodulates the GFSK, does the de-interleaving and error correction, and then converts the digital audio back to analog audio. The stereo audio is output on balanced XLR connectors or via MPX over BNC when the optional Stereo-RDS option board is used. In addition to the audio, the link also sends a RS232 (9600baud) through, it can be used e.g. to update the RDS encoder at the FM transmitter site.

Both STAT1800 and STAR1800 have a RS232 (5V level) debugging output port. It provides continuous data from all internal measurements. This can be used to connect a logging PC for continuously logging of the link quality. STAR/STAT1800 have several watchdog systems to ensure that reliability is very high. If there is no audio on the link or if the receiving signal is lost, then the STAR1800 can switch in a backup audio source automatically. The display shows the operating status: e.g. ‘normal operation’ or ‘shorted coax’. Two measurement screens show all important operating parameters.

Benefits

• Completely legal
• Complete free to use
• No notification
• Distance range and wave propagation identical to 1500MHz band
• Perfect digital audio quality
• Limited audio delay
• Easy and quick installation with low cost coax cable
• Optional internal stereo and RDS coder (MPX output)
• No line of sight nessecairy

Now also available with built in Stereo-RDS encoder board!

Modulation type: GFSK
Bandwidth: 300kHz (98.7% of power), 480kHz according to spectrum mask EN301-357 Frequency: 1795.3 to 1799.7 MHz in 100kHz steps
Temperature range: 0 … 40°C, for TX Octenna: -20 … 50°C
Further technical specifications: according to EN301-357 STAR1800:
Audio output: XLR balanced (can also be used unbalanced, leave unused open) Output level: fixed, 3Vptp differential, with 50% input level in STAT1800 Input for backup audio: cinch, stereo, level adjustable, audio is switched
Output for backup: 230V/50Wmax enabled if backup is required to operate Allowable coax loss to maintain sensitivity: 0 to 14dB
Sensitivity on the (internal) antenna terminals: -2dBuV (-109dBm) (for perfect stereo, fading margin= 0) Target reception, including fading margin: 5dBuV (-102dBm) Maximum signal on (internal) antenna terminals to avoid saturation: – 20dBm
Frequency: 1795.3 to 1799.7 MHz in 100kHz steps
Temperature range: 0 … 40°C, for TX Octenna: -20 … 50°C
Further technical specifications: according to EN301-357