This is a beautiful machine, recently upgraded to 250 watts for the 200 watt version we sold for over a decade. There are lot of these units going strong in the world working 24/7 without a hiccup. The internal 250 watt amplifier blocks will operate with ease at full power 24 hours a day non stop in any country and with any AC voltage in the world. The front panel has a neat little meter panel lit up in blue to indicate forward and reflected power.
The RF output power of the amplifier automatically folds back, very fast to a safe level when there is fault condition of poor SWR and return loss of any level for any duration of time. When the fault clears the amplifier restores to full power.
This unit is designed with high reliability in mind to work in hot countries close to the equator. The cooling system incorporates at the back three 60 mm fans and at the front one 80mm fan to keep the heatsinks in this unit cool to touch by hand. Many of these units are operational for years in Nigeria without any issues. If this is not enough, if any of the fans were to fail, and let's face it and be honest, that could happen after a few years of use, the internal temperature sensor will reduce the amplifier power down to a safe level to keep the temperature in check until the fan has been replaced by a new one.
The enclosure is made in strong 16 gauge steel, powder coated and baked in satin black. This leaves a tough, durable surface that will never rot or corrode and be cleaned to shine for decades. The front panel is 19 inch across and 2U (3.5 inch) high with a depth of 12 inches, so it will fit with ease into a standard rack. It is very strong and difficult to damage even under extreme handling.
The frequency and power level is easy to change, but not so easy that somebody with no experience can just press a button on the front, that would be too easy and dangerous. We reached a compromise with this, we placed these controls on the underside of the unit. To get to them, just slide the unit out of the rack, flip it over and the little dip switches will allow you to change the frequency and a trim pots for the power and deviation level.
The stereo version with audio processing and limiting is available or the straight raw composite MPX version. If you're not sure which version you need, then it's a high probability that need the stereo version with audio processing and limiting. In any case the stereo version has the option of MPX input, it can be used for both. If you wish to connect the unit to external processing such as Optimod, Inovonics, Breakaway, StereoTool etc you should use the MPX version More Information HERE.
STEREO VERSION WITH AUDIO PROCESSING
MPX / COMPOSITE INPUT (NO PROCESSING)
250 Watts with a high performance well installed antenna is a typical set up for a local radio station for a big town or small city. In rural areas up to 45 miles range is possible.
On delivery the equipment is ready to plug in and use with any suitable 50 ohm antenna system such as our:
4.8dBi 2 DIPOLES
7.8dBi 4 DIPOLES
10.8dBi 8 DIPOLES
4.8dBi 5/8 ANTENNA
-0.8dBi CIRC. DIPOLE
Our 500W EIRP package includes this transmitter complete with antennas and cables ready to go. It is a full system that complies with the regulations of the European Union and most other countries in the world.
The stereo version with audio processing and limiting meets all the regulatory standards required out of the box and pre configured. In fact if you send us a copy of your permit and it's conditions, we will set it up exactly to the specification. This equipment complies with EU/CE harmonised standards and FCC technical requirements for FM broadcasting. More information HERE
All stated measurements were made at 220VAC at 27 Degrees Celsius ambient temperature unless stated.
|Power Output||Adj. 1-250 Watts into 50 ohms|
|Spurious Emissions||Less than -75 dB ref to carrier|
|Harmonic Emissions||Less than -70 dB ref to carrier|
|Freq Stability||+/- 1 KHz max. typ. +/-300 Hz|
|Deviation Sensitivity Stability||+/-2 % max|
|Freq Fine Adj||> +/- 1000 Hz|
|Freq Range||87.5 to 108 MHz in 100 KHz steps|
|Out of Lock RF Muting||Less than -70 dB ref to carrier|
|Residual AM||Less than 0.5 %|
|Synchronous AM||Less than 0.5 %|
|RF Ruggedness||Any VSWR phase or length of time|
|Operating Temp||-20 to +40 Deg C|
|Pre-emphasis||(50 uS/ 75 uS/ None) Selectable|
|Audio Input Connector||Phono/ RCA type unbalanced sockets|
|Audio Input Sensitivity||+4 dBu for +/- 75 KHz dev.|
|Version||MPX||Stereo and Audio Processor|
|Signal To Noise Ratio||80dB||65dB|
|Audio Distortion||0.2% THD Max||0.2% THD Max (at MPX section)|
|Input Voltage||90-264 V AC 135-370 V DC 47-63 Hz|
|Input Power||500W for 250W RF OUT with RF SWR less than 1.5|
|Working Humidity||20-90% RH non-condensing|
|Safety Standards||UL60950-1 TUV EN60950-1 BSMI CNS14336 CCC GB4943 J60950-1 approved|
|EMC Emission||Compliance to EN55022 class B EN61000-3-2 3 FCC PART 15 / CISPR22 class B CNS13438 class B GB17625.1|
|EMC Immunity||Compliance to EN61000-4-2 3 4 5 6 8 11 light industry level criteria A|