MT4 is accomplished by true FM transmitting. A variable gain cell amplifier is used for low distortion audio without clipping (less than 2%). Compression begins at 4.8 KHz and hard limiting will occur at a level of 5 KHz (factory set values). In hard limiting the modulation is held constant for input levels of greater than 30 DB. Unlike most transmitters today the MT4 uses a MOS FET for the final transistor. The MOS FET has a much lower noise floor (typically 3 times lower) and is not subject to thermal runaway as bi-polar are. The MOS FET used in the MT4 is capable of withstanding up to a 30:1VSWR. When configured for high power operation the MT4 is supplied with a multiple section low pass filter to suppress harmonics.
Voltages are decoupled in all stages to prevent noise pickup using ferrite beads for high frequency and capacitors for low frequency rejection. The circuit board also has copper ground planes on the top and bottom with multiple feed through points for excellent R.F. grounding.
Comes mounted in an R.F. tight enclosure with feed through capacitors for both audio and power supply lines. The R.F. out is supplied to an SO239 connector for VHF and TYPE N standard on UHF. All units are factory tested and burned in to your specified frequency before shipment. Their 1-year warranty is our statement of commitment to quality.
136-174MHz, 216-250MHz (VHF), 420-520MHz (UHF)
@ 13.8 V
@ 24 V
@ 13.8 V
@ 24 V
Parallel resonant crystal (22 pf load) capacitance, HC-25/U holder. Proportional oven used in FCC type accepted units.
MOS FET capable of withstanding 30:1 VSWR
Direct FM. Variable gain cell amplifier for audio compression and limiting with low distortion. Adjustable from 0-7 KHz.
.0005% (-30c to 60c), .0001% with optional proportional oven
Greater than 65 DB below rated output
Greater than 90 DB below rated output
Greater than 90 DB below rated output in high power mode at 600 KHz from output frequency.
Within 3 DB of EIS standard 6 DB / octave pre-emphasis from 300 Hz to 2700 Hz. Less than 2% distortion.
Continuous, (all our products are rated for continuous commercial duty)
5 F 3
LOW NOISE MOS FET
90% DUTY CYCLE
SHIELD OSCILLATOR / MULTIPLIER
PROVISIONS FOR INTERNAL CTCSS
All ACS products are guaranteed in materials and workmanship for 1 year from the date of purchase. Please
contact us for complete details.