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.
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.
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.
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.
FM 300W AMPLIFIER
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.
- Input power 5W
Output power 275W
Comply with ETSI ETS
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.
· 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.
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.