5314027917

83IG Series specilicalions

83KM/IB FM Transmitters

The 831G Transmitters are offered in two configurations. The first is a 20-kW version, and the second. an upgraded 22.5-kW unit. This transmitter linę is the basie equipment used to provide the various high power transmitters that Collins offers. Ali of the features that are offered in the 831 H linę of transmitters are present in the 831G linę, and in addition, the following operational advantages are of interest.

The 831G-1/1B transmitters have only three tubes-two in the driver. one in the finał. The entire transmitter is contained in one three-bay cabinet that lends itself to restricted space. and ease of maintenance. A high-Q finał cavity and an efficient self-contained low-pass filter provide attenuation of harmonics that is far below FCC regulations. Ali tuning and control functions are on the front panel, thus simplifying operation and maintenance. The control panel may be removed from the transmitter and located up to 50 feet from the unit.

As in all of the Collins FM transmitters, the 831G series uses the Collins 310Z Exciter to provide a signal that is second to nonę for quality and reliability. This all solid State exciter added to the proven quality of the831G-1 or 831G-1B Power Amplifier. offers the broadcaster savings in cost of operation that is unexcelled.

Output Power......... 831G-1: 20 kW

831G-1B: 22.5 kW

Output Impedance ...... 50 ohms. VSWR 2:1 maximum.

Frequency Rangę....... 88-108 MHz.

Frequency Stability...... ±1000 Hz.

Modulation Capability ....    ±100 KHz.

Audio Input Level ...... 10 dbm ±2db.

Audio Freouency Response . . Complies with FCC standard

pre-emphasis curve.

Audio Frequency Distortion . Monaural: prod test spec is 1.0%

or less (typical 0.5% or lessl 50 to 15,000 Hz.

Stereo Separation....... 35 dB minimum, 50 to 15,000 Hz

<39 dB typical)

Harmonie Attenuation ....    -80 db minimum.

FM Noise Level........ 65 db below 100% modulation

(±75 kHz).

AM Noise Level........ -55 db RMS.

Altitude............ Operating 7500 ft. @ 30 C.

Non-operating 10.000 ft.

Power Source......... 200-250 volts ac 50/60 Hz

three-phase. Available taps on transformers are for 200, 210, 220,230, 240, and 250 volts.

Permissible Linę Voltage . . .    ⁺S%. In addition, each phase

voltage shall be within 5% of the average of all three phases.

Power Reguirements ..... Nominał 20 kW output requires

35 kVa at 097 power factor; nominał 22.5 kW output requires 39 kVa at 0.97 power factor.

Size:.............. 68-15/16" (175.1 cm) H; 71-1/2"

(181.6 cm) W; 27-1/2" (69.8 cm)

D.

Weight:............ 2400 Ibs (1045 kg).

831G-1........... FM Transmitter, 20 kW

831G-1B.......... FM Transmitter, 22.5    kW

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831G Błock Diagram

831G FM Transmitter

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