Transcom
 
 
Surplus  Equipment

Used AM  Transmitters

 
Used FM  Transmitters
 
 
 
 
 
 
 
 
 


                                                 CCA 10 kW
            Medium Wave & Short Wave AM Broadcast Transmitter AM 10,000 F


CCA 10 KW SW
 
* High Efficiency Power
Amplifier Circuitry
* Easy-to-Service and
Understand Circuitry
* Rugged Construction with
High Quality Components
* Conventional, Heavy-Duty
Power Supplies
* Designed for FCC, DCC, and
CCIR Requirements
* Conventional, Dependable,
High Level Plate Modulation
* Power Line Phase Drop-out
Protection
* Step-Start Operation

CCA AM TRANSMITTERS
 
For over twenty five years, CCA transmitters have had the best TIME-PROVEN
record for reliability. "Battleship" type construction, using high quality,
conservatively rated components, is one reason CCA transmitters perform better
and longer than others. Design is simple and easy to understand. Plate
modulation is known for its dependability and world-wide familiarity. It also
has a very pleasing sound and does not have the problems associated with other
newer and higher voltage techniques.
Conventional relays are still the most reliable way to control power equipment
in the typical transmitter environment. Vacuum tubes (valves) are still more
cost effective for operating in severe world-wide conditions. With a
conventional, conservatively rated power supply, relay control and dependable
plate modulation, CCA AM Transmitters are more immune to the hazards of the
broadcast environment.

GENERAL DESCRIPTION
 
The CCA AM 10,000 F is part of a family of medium wave and HF transmitters
designed for use in all regions of the world. These reliable transmitters use
solid state devices up to the RF power and modulator stages. The entire
transmitter is contained in two cabinets. Extra bypassing and special HF
techniques are used in the HF version.

EXCITER

A standard, crystal oscillator is used at its fundamental frequency or
digitally divided down to the required carrier frequency, which ever is more
appropriate. A programmable, frequency synthesized oscillator is optional.

DRIVER

 The driver is solid state, except in the 15 kW and HF version where the extra
 drive of a buffer stage is needed.
 
POWER AMPLIFIER
 
 The power amplifier uses the 4CX15000A, operating as a plate modulated class C
 amplifier. The 4CX5000A is used in the 5 kW version. Rugged silver plated
 inductors and vacuum capacitors are used in a Pi-L output network.
 
AUDIO PREAMPLIFIER/DRIVER
 
 A solid-state module contains the audio preamplifier-modulator section, which
 amplifies the nominal +10 dBm input signal to the level required by the AM
 differential amplifier.
 This high fidelity, solid-state module uses transistors in complimentary-
 symmetry. By careful attention to the reduction of cross-over distortion, a
 high fidelity signal is available for the modulator tubes.

MODULATORS

 The modulator power amplifier stage consists of two tetrode tubes (type
 4CX5000A) connected in push-pull and operated in Class AB1 mode. A front panel
 control permits adjustment of filament voltage. Modulator cathode currents are
 metered. Individual grid bias adjustment controls are provided.
 
POWER SUPPLIES
 
 The main power supply uses a three phase rectifier circuit. Rugged silicon
 rectifiers are used throughout.
 CONTROL/OVERLOAD/RECYCLING SYSTEM
 A relay control system incorporates full overload protection and automatic
 three overload recycling with visual indicators which display the status of all
 critical circuits. In the event of intermittent or short term overloads, the
 circuit in which the malfunction occurred is immediately identifiable. The
 recycling system will automatically return the transmitter to service in the
 event of a momentary interruption of primary power or an overload condition.
 For overloads occurring three times within a one minute time interval, the
 recycling system will turn the transmitter off, with a visual indication of the
 circuit in which the overload occurred. The circuit then must be reset
 manually. The control circuit provides an automatic "step start" sequence to
 turn the transmitter on. 'After-cooling' is included as a standard feature.
 REMOTE CONTROL
 Terminations allow interfacing with all standard wire or STL remote control
 systems. These include start/stop and power output control and telemetering of
 PA plate voltage and current and RF output. Terminals are provided for
 monitoring equipment.

 

Nominal Power Output

10 kW

Frequency Range

500 kHz - 2 MHz (2 - 22 MHz)

Frequency stability

5 Hz

Carrier Shift (@ 100% Modulation)

2% Max. (less than 1% typical)

RF Output Impedance (specify)

50 ohms standard

Modulation Capability

125%

AF Input Impedance

AF Input Level (@ 100% Modulation)

600 ohms

+10 dBm Max. (+2 dBm)

AF Response

50-7500 Hz +1 dB 50-10,000 Hz +1.5 dB

AF Distortion

50-10,000 Hz 3% Max.

Noise (below 100% Modulation)

-55 dB

Line Voltage (specify)

208/240/380 V

Line Frequency (specify)

50/60 Hz

Phase

3 (closed Delta)

Net Dimensions

76" W x 71" H x 34" D

Gross Weight

Approx. 3,000 lbs.

Harmonic Attenuation (2nd) (3rd) Others

-90 dB -80 dB -80 dB