AM Broadcast Transmitter Type 417D 50 kW SW

photo Continental Electronics 417 D Continental Electronics' vast knowledge and background in the design, development, manufacture, system plans, installation, and operation of high-power and super-power transmitters have been fully utilized in the design of our Type 417D Transmitter.

Only long-terms reliable components and electron tubes are utilized. The application of simple field-proven circuitry has resulted in a modern high frequency broadcast transmitter which is capable of providing excellent overall efficiency.

Salient features of our Type 417D Transmitter are:

  1. Solid state hybrid circuit is used for the modulator driver, and a broadband solid state RF amplifier is used to drive the IPA amplifier.

  2. Simple, trouble-free air cooling throughout.

  3. Fast frequency change is provided with selection of up to 10 pre-selected frequencies. Tuning transmitter to a new frequency is extremely easy since only five tuning controls are used. After tuning is once accomplished and set as one of 10 preset channels, it can be retuned by activating the appropriate channel without further manual retuning.

  4. Single 4CX35,000C tetrode tube used in the RF final amplifier provides for extreme stability, simplifies circuitry, neutralization and tuning throughout the frequency range.

  5. Maximum reliability due to minimum number of high gain amplifier staqe; final power amplifier and modulator tubes, are operated below 75 percent of their rated plate dissipation. The power supplies all use highly reliable and efficient semiconductor devices in the rectifier assemblies.

  6. New developments in high speed power contactors eliminate the need for expensive high speed vacuum switches for fault interruption with no degradation in performance

  7. Individual instrumentation for all important electron tube functions, rectifier output voltages, primary power voltage and elapsed operation time.

  8. Comprehensive supervisory control and equipment protection system with illuminated pushbutton status signals for all important operating and fault conditions.

  9. Automatic personnel protective system interrupts, then grounds all dangerous voltage when an access door is opened.

  10. Continuous full power operation with specified performance over wide range of environmental conditions.

  11. Compact cabinet design requires a minimum of floor space. Full width doors permit easy maintenance access. Cooling and high voltage equipment occupies a small area close to the transmitter cabinets.

Carrier Output Power 50 kilowatts
Types of Emission Amplitude Modulation (A3) and Frequency Shift (F1)
Types of Modulation High-level plate, Class "AB" modulator
Final Power Amplifier Class "C" operation
Frequency Range 3.2 to 22 MHz
Output Impedance 75 ohms unbalanced or 300 ohms balanced (optional). VSWR less than 1.5:1
Modulation Capability 100%, 50 to 10,000 Hz sinusoidal
Radio Frequency Harmonics and Spurious Radiation Less than 50 mW (Complies with CCCIR Recommendations)
Audio Input Impedance 600/150 ohms, balanced or unbalanced
Audio Input Levels for 100% Modulation +10 dBm at 1000 Hz
Audio Frequency Response ±1 dB from 50 - 7500 Hz @ 90% Modulation
Audio Frequency Distortion Less than 3% RMS, 50 - 7500 Hz @ 90% Modulation
Residual Carrier Noise More than 55 dB (unweighted) below 100% modulation level at 1000 Hz
Carrier Shift Less than 3% at 100% Modulation exclusive of power line variations
Relative Humidity 95 Percent
Altitude 6000 feet above sea level
Power Consumption Unmodulated, 98 kW
30% Modulation, 114 kW
50% Modulation, 125 kW
100% Modulation, 135 kW
Primary Power Requirements 360 to 480 volt, (±5% regulation), three-phase, 50/60 Hz (other on special order)
Power Factor Better than 0.9
Ambient Temperature Range +5°C to +45°C
Specifications may change without notice

RF stages AF stages and modulator
Number Type Number Type
1 4CX35,000C 2 4CX15,000A
1 4CX3000A


ITU Country
ITU Country