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Pyramid Broadcast Equipments
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Pyramid Broadcast Equipments



PYRAMID 20 is high quality broadcast FM modulators whose only difference is the maximum output power. Fully microprocessors controlled, they are designed to work in a real continuous service at any power level within the allowable range Of the two microprocessors, the first one is devoted to measures, frequency programming, output power and modulation linearity control, the second microprocessor is instead entirely devoted to the PLL circuitry.  

The use of microprocessors made possible to realize an analogic FM modulator with exceptional characteristics of linearity to frequency and very accurate readings of output power, modulation and SWR.  

A digital circuit controls the modulation, and a circuit limiter is present to exactly to limit the frequency deviation within the actual norms.

Technical Description

After the ON switch has been pressed, the PYRAMID modulators carry out a procedure that sequentially checks the internal circuits. All this job is performed in about 4 seconds and if the check up procedure has been successfully completed, the modulator is then activated.   

Most of the settings are possible using the soft keys of the front panel keyboard. On the rear panel are placed the input and output connectors.   From the front panel it's also possible to access the two precision trimmers regulating the output power (Low and High) and to monitor the various functions of the modulator with the LCD display.


Pyramid 25


Specifically designed for the tight International norms, it is already homologated in several European Countries.

It combines an excellent programmability to the greatest ease of connection; it has several display lectures, allowing adjustable levels from display, to adapt to any input source or transmission options.

Password scaled levels are foreseen to access to the several programming sections.

Principal technical features:

  • The best quality price ratio.
  • mP controlled
  • Extremely low distortion THD, IMD
  • Built-in stereo encoder
  • Easy to use: comprehensive monitoring of all relevant parameters and setting values.
  • ETSI ETS 300-384, CCIR & FCC compliant.




Comply with ETSI ETS 300-384


It is based on a practical two transistors push-pull circuit and it is suitable for critical situation use; oversized components designed for continuous duties.
Strong construction and stableness, it is suggestible to drive higher power amplifiers.

Other parameters:

- Input power 5W

- Output power 275W


Comply with ETSI ETS 300-384

Solid State broadband amplifier made of two 300W coupled modules to secure a wide margin of efficiency.
The performances are higher than the ones declared for units in the market with similar nominal power.
As for FM 300 W has the same output power auto-limiter, proportional to R.O.S. and in case of high values, break down the output power up to the original starting value.

Other parameters:

  input power <10W

  output power >500 W



Comply with ETSI ETS 300-384

The PYRAMID 1000 is a tuned RF power amplifier for FM broadcasting using a cavity mounted triode. To maximize linearity and better match, both input and output are tuned. The operation is that as a final or intermediate amplifier stage in a system with a modulator and, eventually, other stages of amplification.

The amplifiers arenormally delivered for a single phase 220V 50 (60) Hz line. The antenna is 50 Ohm nominal and the connector is an LC type.

Technical Description

The used tube is an EIMAC 3CPX800 A7 triode in GG configuration. A largely oversized low pass filter with a minimal insertion loss is incorporated in the apparatus to further reduce harmonics and unwanted emissions. Plate supply is obtained through a full wave rectifier and a capacitive filter.

The plate transformer is PTFE isolated and the amplifier include a soft start circuit.

The voltage for the cathiode biasing is stabilized with a power zener diode. Controls on the operation of the apparatus include suspensions in case of overvalues.
Up to 9 tentatives to self restart after a suspension will be performed automatically, after the 9th failed retry, to increase safety, restart has to be performed manually.

In case of suspensions, the blinking LED indicates which failure occurred and the display the number of occurred events. To maximixe a conortable use, all controls, including PLATE and LOAD, likewise input tuning, are on the front panel.

Please contact us for more Info.