CONTINENTAL ELECTRONICS 418 G DRM

GENERAL DESCRIPTION


photo Continental Electronics 418 G DRM The Continental Type 418G-DRM 100 kW Shortwave Broadcast Transmitter has been designed and developed to provide high performance, optimum efficiency, and long-term reliability in the shortwave broadcast bands. The transmitter can be operated in standard amplitude modulation (AM) mode, AM with Controlled Carrier-level Modulation (CCM), or digital streaming in the DRM mode (when used with the optional DRM Encoder/ Exciter). The CEC 418G-DRM transmitter is a field tested and proven DRM transmitter system.

The Type 418G-DRM 100 kW Transmitter is the direct descendent of a long and successful line of Continental 100 kW broadcast transmitters. The 418G-DRM employs the highly refined and reliable RF sections of its predecessors. The RF amplifier tube of the 418G-DRM is the 4CV100,000C tetrode, which is one of the longest life high-power tubes available.

FEATURES
TECHNICAL SPECIFICATIONS
ELECTRICAL
RF Carrier Output Power (A3E) 100 kW (400 kW PEP) on all frequencies through the 3.90 to 22 MHZ range
Reduced RF Carrier Output Power (A3E) 25 kW - 100 kW
Power Source Customer specified: 360-480 VAC, 50/60 Hz, 3-phase, other voltages available on request
RF
Efficiency The overall efficiency of the Type 418G DRM Transmitter measured as an average of ten frequencies over the range of 3.9 - 26.1 MHz at 100 kW carrier power level will not be less than 67% with any depth of modulation. (Lower at lower power levels)
Frequency Range 3.9 - 22 MHz continuous in 100 Hz increments. 3.9 - 26.1 MHz, optional, 2.3 - 16 MHz, optional
Tuning Time An average of 10 typical frequency changes takes less than 30 seconds each
Standing Wave Ratio Rated for 2.0:1 VSWR at full power or any customer selected VSWR below 2:1
RF Output Impedance 300 ohms balanced (Standard); 50 or 75 ohms unbalanced Optional
Carrier Level Shift (A3E) Less than or equal to +/-3% shift at 100% tone modulation with 1 kHz sine wave exclusive of power line variations
RF Spurious Less than 50 mW. Out of band emissions in compliance with CCIR 328-5
ENVIRONMENT
Ambient Temperature Range Indoors: +40 to +111°F (+5 to +45°C)
Outdoors: +14 to +111°F (-10 to +45°C)
Relative Humidity Range 0 to 95% relative humidity, non-condensing
Altitude Up to 6,000 ft. (1,829 m) above sea level
Cooling Water, heat exchanger (supplied), and air cooling
AUDIO
Modes of Emission A3E and DRM, Standard, SSB Optional
Modulation Method High efficiency all-solid-state step modulator using EER for AM/PM Modes
Audio Input Requirements Adjustable from -8 to +10 dBm for 100% AM modulation
Audio Input Impedance 600 ohms, balanced. Other impedances on special order
Audio Response (A3E) +1/-1.5 dB from 50 Hz to 7500 Hz at 70% modulation
Audio Harmonic Distortion (A3E) Less than 3.0% at 50-90% modulation from 50 to 7500 Hz
Carrier Noise -56 dB, unweighted, referenced to 100% modulation with a 1 kHz tone
Controlled Carrier Level Modulation (CCM) The Type 418G DRM Transmitter has the capability of operating with variable carrier power. This technique scales the amplitude of the carrier to the percentage of modulation. The carrier can be reduced as much as 6 dB below the rated value without audio distortion and can be a major cost saving to the user
Modulation Capability 100% sinusoidal modulation at frequencies from 50 to 7,500 Hz, for ten (10) minutes per hour. Up to 70% modulation on a continuous basis
DRM
RF Output Power (DRM) 50 kW RMS, 400 kW PEP with 9 dB Crest Factor
DRM: Meets all IEC PAS62272-1 & ETSI REF.ES 201 980 V.1.2.1 2002-07 specifications See the exciter brochure for a full list of features. DMOD3 DRM Exciter is totally integrated into the transmitter
DRM Modes All DRM 9 kHz and 10 kHz bandwidth modes are supported
MER (Modulation Error Rate) -30 dB, or better
SSB Option
RF Output Power (H3E and R3E) 200 kW PEP Two-Tone
High Efficiency H3E and R3E (LSB, USB and ISB) using EER (Envelope Elimination and Restoration)
Intermodulation Distortion (H3E & R3E) At least -35 dB relative to either tone of a two-tone test signal
Carrier Reduction (H3E & R3E) -6 dB to -24 dB relative to full carrier or full Carrier suppression
Specifications may change without notice

TUBE COMPLEMENT
RF stages AF stages and modulator
Number Type Number Type
1 4CV100,000C

1 4CX3000A



THIS TYPE OF TRANSMITTER IS INSTALLED IN THE FOLLOWING COUNTRIES

ITU Country
ITU Country
flag AUS AUS AUSTRALIA flag KOR KOR KOREA SOUTH
flag MDG MDG MADAGASCAR flag MLA MLA MALAYSIA
flag ROU ROU ROMANIA flag USA USA USA