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BE FM-3.5A, One Tube 1.5KW to 3.8KW FM Transmitter

TECHNICAL SPECIFICATIONS

 

 

 GENERAL

 POWER OUTPUT: 3.5kW (from 1.5kW to 3.8kW).

FREQUENCY RANGE: 87.5 to 108 MHz, tuned to specified operating frequency. Exciter programmable in 10kHz increments.

RF OUTPUT IMPEDANCE: 50 ohms (others on special request).

OUTPUT CONNECTOR: 1 5/8" EIA flange.

VSWR: 2:1 maximum (will operate into higher VSWR with automatic power reduction).

FREQUENCY STABILITY: +/-30OHz, 0 to 500C, temperature compensated crystal oscillator.

TYPE OF MODULATION: Direct frequency modulation of carrier frequency.

MODULATION CAPABILITY: Greater than 200 kHz.

MODULATION INDICATION: Peak reading, color coded, LED display with base band over-modulation indicator.

EXCITER.  Solid state, 30 watt output, Model FX-30; incorporates digitally programmed synthesizer (10kHz increments).

PRE-EMPHASIS:    FCC 75uS, CCIR 5OuS (where specified), or 25uS (Dolby).

ASYNCHRONOUS AM S/N RATIO: 55dB below reference carrier with 100% AM modulation @ 40OHz, 75 microsecond de-emphasis. (no FM modulation present).

SYNCHRONOUS AM S/N RATIO: 4OdB below reference carrier with 100% AM modulation @ 40OHz, 75 microsecond de-emphasis. (FM modulation 75kHz @ 40OHz).

TUBE COMPLEMENT: 4CX3500A (1).

RF HARMONICS: Suppression meets all FCC/DOC requirements and CCIR recommendations. POWER SUPPLY RECTIFIERS: Silicon.

 

ELECTRICAL/MECHANICAL

 AC INPUT POWER: 208/24OV, 50/6OHz, single phase. (Taps for 196 to 252V). (Other voltages are available upon request).

POWER CONSUMPTION: 6.8kW @ 0.9PF @ 3.5kW output.

SIZE & WEIGHT: 34.5" W (87.63 cm) x 70" H (177.8 cm) x 37.25" D (94.61 cm).  Weight 1050 lbs. (477 kg) unpacked; 1210 lbs. (550 kg.) packed.

CUBAGE:     Net 53 cu. ft. (11 .5 cu. m.) Packed 60 cu. ft. (2 cu. m.)

ALTITUDE:   7500 ft. @ 50 Hz/ 10,000 ft. @ 60 Hz.

AMBIENT TEMPERATURE RANGE: - 10C to +50C.

FINISH: BE blue with anodized aluminum control center panel and anodized aluminum trim.

 

*MONAURAL OPERATION

 

AUDIO INPUT IMPEDANCE: 600 ohms balanced, resistive, adaptable to other impedances, 50 dB common mode suppression.

AUDIO INPUT LEVEL: +10 dBm nominal for 75 kHz deviation @ 400 Hz.

AUDIO FREQUENCY RESPONSE: 0.5 dB, 30 Hz to 15 kHz, selectable flat, 25, 50 or 75 microsecond pre-emphasis.

HARMONIC DISTORTION: 0.08% or less, 30 Hz to 15 kHz.

INTERMODULATION DISTORTION: 0.08% or less, 60 Hz/7 kHz, 4:1 ratio.

TRANSIENT IMD: 0.1% or less (square wave/ sine wave).

FM S/N RATIO: 75 dB below 75 kHz deviation @ 400 Hz (78 dB typical) measured in a 30 Hz to 15 kHz bandwidth with 75 microsecond de-emphasis.

 

*WIDEBAND COMPOSITE OPERATION (Thru FM-3.5A using FX-30)

 

COMPOSITE INPUTS: 3 total, (1) unbalanced and (1) balanced plus front panel test.  BNC connectors.

COMPOSITE INPUT IMPEDANCE: 10 k ohm, nominal, resistive.

COMPOSITE INPUT LEVEL: 3.5 VP-P nominal, for 75 kHz deviation.

COMPOSITE FM S/N RATIO: 75 dB below 75 kHz deviation @ 400 Hz (78 dB typical).  Measured in a 30 Hz to 100 kHz bandwidth with 75 microsecond de-emphasis.

COMPOSITE HARMONIC DISTORTION: 0.08% or less (.04% typical).

COMPOSITE INTERMODULATION DISTORTION: 0.08% or less (.04% typical).

COMPOSITE TRANSIENT IMD: 0.1% or less (square wave/sine wave).

COMPOSITE AMPLITUDE RESPONSE: 0.1 dB, 30 Hz to 53 kHz.

COMPOSITE PHASE RESPONSE: 0.5 from linear phase, 30 Hz to 53 kHz.

COMPOSITE GROUP DELAY: 390 nanoseconds 25 nanoseconds, 30 Hz to 53 kHz.

COMPOSITE SLEW RATE: 12 V/microsecond (symmetrical).

 

*STEREO OPERATION (Thru FM-3.5A using FS-30 Stereo Generator)

AUDIO INPUT IMPEDANCE: 600 ohms balanced, resistive, floating. (Adaptable to other impedances).

AUDIO INPUT LEVEL: +10 dBm, 1 dB for 100% modulation @ 400 Hz. (Adaptable to other input levels).

AUDIO INPUT FILTER: 15 kHz LPF with delay equalization for minimum overshoot.

FREQUENCY RESPONSE: 0.5 dB, 30-15,000 Hz, 75 usec pre-emphasis (flat, 25 or 50 usec pre-emphasis selectable).

TOTAL HARMONIC DISTORTION: 0.08% or less, 30-15,000 Hz.

 

INTERMODULATION DISTORTION: 0.08%, 60 Hz/7 kHz; 4:1 ratio.

TRANSIENT INTERMODULATION DISTORTION: 0. 1 % (Squarewave/sine wave).

FM NOISE: 72 dB or better below 100% modulation @ 400 Hz, 75 usec de-emphasis.

STEREO SEPARATION: 45 dB or better; 30-15,000 Hz (sine wave).

DYNAMIC STEREO SEPARATION: 40 dB or better; 30-15,000 Hz (normal program content).

LINEAR CROSSTALK.  Main to Sub/Sub to Main due to amplitude and phase matching of left and right channels, 30-15,000 Hz, 45 dB minimum below 100% modulation.

NON-LINEAR CROSSTALK.  Main to Sub/Sub to Main due to distortion products. 70 dB minimum below 100% modulation.

38 kHz SUPPRESSION: 70 dB minimum below I 00% modulation.

PILOT STABILITY: 0.5 Hz, 0 to 50C.

MODES: Stereo, Mono L+R, Mono (L) and Mono (R) remote controlled (See FS-30 data sheet for full details).

 

'SCA OPERATION (Thru FM-3.5A using FC-30 SCA Generator)

 

MODULATION: Direct FM

SUBCARRIER FREQUENCY: 67 kHz (39 to 95 kHz to order).

SUBCARRIER FREQUENCY STABILITY: 0.5% (330 Hz @ 67 kHz), 0 - 50C.

SUBCARRIER HARMONIC CONTENT: Less than 0.3%.

SUBCARRIER ENVELOPE DECAY: Greater than 100 msec. from 90% to 10% sub-carrier levels.

MODULATION CAPABILITY: 20% of sub-carrier frequency.

AUDIO INPUT IMPEDANCE: 600 ohm balanced resistive.

DATA INPUT IMPEDANCE: 75 ohm unbalanced resistive DC coupled.

INPUT LEVELS: (Audio) Adjustable, +10 dBm to -10 dBm for 6 kHz deviation @ 400 Hz. (Data) Adjustable, 1.0 to 4.0 V p-p for 6 kHz deviation (D.C. coupled).

PREEMPHASIS: (Audio) 150 microseconds standard (75 usec with internal jumper). (Data) no pre-emphasis.

FREQUENCY RESPONSE: (Audio) 0.5 dB, I0-10,000 Hz, exclusive of audio low-pass filter. (Data) 0.5 dB, dc-10,000 Hz.

AUDIO LOW-PASS FILTER: Sixth order, -3 dB @ 4.3 kHz, standard (resistor changes for other values).

DATA LOW-PASS FILTER: Same as AF filter or may be bypassed.

TOTAL HARMONIC DISTORTION: Less than 0.5% throughout AF pass band.

INTERMODULATION DISTORTION: Less than 0.5%, 6OHz/7kHz; 1:1 ratio (audio pre-emphasis and LPF bypassed).  Typical 0.1%.

CROSSTALK, SCA TO STEREO: -60 dB or better below 100% modulation of left or right. 75 usec de-emphasis.

CROSSTALK, STEREO TO SCA: -50 dB or better below 6 kHz deviation of SCA using 150 usec de-emphasis and FS-30 stereo generator.

FM NOISE: 72 dB below 6 kHz deviation @ 400 Hz (150 usec de-emphasis).

AUTO MUTING LEVEL.  Adjustable from 10 to 30 dB below program level.

AUTO MUTING DELAY: Adjustable, 0.5 to 10.0 seconds.

(See FC-30 data sheet for full details).

 

*Through FM-3.5A Transmitter using Model FX-30 Exciter, FS-30 Stereo Generator and FC-30 SCA Generator as applicable.