| TECHNICAL SPECIFICATIONS |
| ELECTRICAL |
| RF Carrier Output Power (A3E) |
500 kW on all frequencies through the 3.90 to 26.1 MHZ range |
| Reduced RF Carrier Output Power (A3E) |
The Type 420D DRM Transmitter can be operated at any power level between 75 and 500 kW with the controls provided |
| Power Source |
4160 VAC, or 11,000 VAC, 3 phase, three wire, 50/60 Hz. Other voltages on special order. Mains power requirement is 1200 kW with 100% tone modulation condition at 0.95 lagging power factor |
| RF |
| Efficiency |
The overall efficiency of the Type 420D DRM Transmitter measured as an average of ten frequencies over the range of 3.9 - 26.1 MHz at 500 kW carrier power level will not be less than 75% with any depth of modulation. (Lower at lower power levels) |
| Frequency Range |
3.9 - 22 MHz continuous in 100 Hz increments. 5.8-26.1 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 dB from 50 Hz to 5000 Hz at 70% modulation or modulation level. +1/-1.5 dB, 5000 - 7500 Hz |
| Audio Harmonic Distortion (A3E) |
Less than 3.5% at 50-90% modulation from 50 to 7500 Hz; less than 4.5% at 90-100% |
| Carrier Noise |
-56 dB, unweighted, referenced to 100% modulation with a 1 kHz tone |
| Controlled Carrier Level Modulation (CCM) |
The Type 420D 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) |
250 kW RMS, 2000 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) |
1000 kW PEP Two-Tone |
| High Efficiency |
H3E and R3E (LSB, USB and ISB) using EER (Envelope Elimination and Recovery) |
| 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 |
The Continental Electronics Type 420D-DRM Transmitters are versatile, state-of-the-art, high-efficiency 500 kW DRM shortwave transmitters capable of being operated in standard amplitude modulation (AM), Controlled Carrier-level Modulation (CCM) or digital streaming in the DRM mode (when used with the optional DRM Encoder/ Exciter).