BUCHAREST, Romania — My company, Laet Exim, a broadcast systems integrator based in Romania, bought and installed for a client several CTE Digital Broadcast VL series air-cooled FM radio transmitters of 2.5 kW and 5 kW power. The VL series transmitters range from 2.5 kW up to 10 kW.

We recommended the VLs upon our technical and economic comparisons. The price that we paid was reasonable and the delivery time was two weeks from the order confirmation. The transmitters have been installed in five sites, all of them some distance away from the capital city, Bucharest, in rural areas where the reliability of the electrical grid is questionable.

Easy installation

Prior to the decision to choose CTE, we asked the company for detailed literature about their equipment and the complete manuals for our prepurchase evaluation. We analyzed the design of these transmitters, where the smart modularity concept was the most evident feature.

To simplify maintenance operations, the RF amplifiers and the power supply unit are separated.

Installation and operation of the transmitters proved easy. The user guide was helpful, something that can’t always be said. It included instructions for safe, fast and successful installation for both the 2.5 kW and 5 kW FM transmitters.

An attractive bonus for us, with no increase in the price, was the inclusion of a remote control and monitoring interface for IP networks (SNMP-compatible). This allows for the management of many operations using a simple Web browser.

CTE’s exciters for the VL series offer an AES/EBU digital input, remote control and capability for n+1 systems. In the design, a special effort was devoted to achieve friendly and fast routine maintenance, a much appreciated aspect for us. Frequency and other operational parameters can be set by an intuitive menu that is controlled by four buttons and displayed by an LCD screen on the front.

To achieve power, RF stages of 1.3 kW nominal power are used. Each of them includes four SD2942 next-generation MOSFETs. At our lab in Bucharest, we performed tests that measured impressive high linearity. We have also found out that each module includes a control loop with a high-speed reaction time to protect the equipment against overheating or excessive SWR. These protections are independent with respect to the microprocessor.

The power supply is composed by three identical boards connected in parallel. It has the standard dimensions of 19 inches and is 2 RU.

The overall depth is 71 centimeters deep and just under 14 kilograms in weight. Such compactness and reduced weight are sufficient to carry the unit, even by one person.

Since installation all of the equipment has been running at full power, all day long, without disruptions or inconveniences. Our customer is happy because he has noticed a 30 percent reduction in the bill for electricity compared to the previous transmitters. Power spikes and instability in the mains have had no impact on the reliability and no variations in the signal have been noted.

Upon our overall positive experiences impressions, we recommend VL series transmitters from CTE Digital Broadcast.

Marius Marin is senior engineer and owner of Laet Exim.

For information, contact Enrico Antoniazzi at CTE Digital Broadcast in Italy at +39-02-96738811 or visit www.ctedb.it.