General view of the modulator

View with the cover open

Top view with the cover open

View of the packaging

Double sideband modulator MT47 has a microprocessor control - the choice of output channel is performed with two buttons (after opening the top cover). The channel number or any changeable parameter is displayed on the LED display and stored in non-volatile memory. Use of quartz-stabilized PLL practically eliminates frequency error. There is a possibility to protect the modulator against unauthorized change of the preset parameters.
The modulators can be connected in cascade. Their RF signals can be combined with terrestrial TV channels (it requires to match the levels of terrestrial TV signals with the RF output levels of the modulators, as well as to ensure adequate frequency spacing).

In comparison to the previous series, these Terra modulators can provide compatibility with many versions of the PAL system.

Adjustment options:
- video carrier frequency,
- RF output level,
- audio subcarrier frequency,
- A/V ratio,
- standard deviation (+/-50 kHz) of audio carrier for input level 150-775 mV

The modulators can be successfully used both in home antenna installations as well as in small-sized MATV systems. Meticulous quality control in Terra company makes these devices virtually failure-free.

Name		MT41	MT42	MT47
Code		R871741	R871742	R871747
Video input	frequency range	20 Hz - 6 MHz
	level / impedance	1 V +/- 1 dB at 75 ohm
Audio input	frequency range	20 Hz - 15 kHz
	level adjustment	+ 1 ... -14 dB
	level (adjustable) / impedance /  standard deviation	775 mV RMS / 10 kohm / 50 kHz
RF output	level (typical) / impedance	90 dBuV / 75 ohm	85 dBuV / 75 ohm
	level adjustment	0 ... -20 dB
	PAL version	G/H/I/L/K/M/N/Australia	B/D/L/H/I/M/N/Australia	B/G/D/K/H/I/L/M/N/Australia
	frequency range	470 - 862 MHz	170 - 300 MHz	170 - 300, 470 - 862 MHz
Carrier frequency error		+/- 50 kHz
Audio subcarrier frequency		4.5; 5.5; 6.0; 6.5 MHz
Fine tuning range of video carrier frequency		+/- 2.25 MHz,  0.25 MHz step
RF loop-through loss (SAT / Terr)		2.5 / 1.5 dB
RF loop-through frequency range		47 - 2150 MHz
Frequency response variation (video)		+/- 1 dB
A/V ratio		12/16 dB
Amplitude modulation depth (typical)		81 %
SNR (weighted)		>= 55 dB
Supplying voltage / power consumption		230 VAC 50 Hz 2.5 W
Operating temperature range		-10 ... +50 deg C
Dimensions / Weight		133x73x39 mm / 0.36 kg