Codan Radio Communications VT-3A130-S-FSH User Manual

VT-3A130 Amplifier Instruction Manual

1-1

The VT-3A130 Amplifier provides the final stage of RF amplification and filtering for the VT-3A
Transmitters. The output power is 1.0 - 4.0 Watt adjustable (carrier only). The amplifier operates
over 118MHz - 138 MHz frequency range without tuning.

Output filtering for the VT-3A130 Amplifier is provided by an Output Lowpass Filter Board. The
Output Lowpass Filter Board is mounted in a separate compartment of the amplifier case in order to
provided maximum attenuation of harmonic and other spurious signals.

Refer to section 4.1.2  "VT-3A130 Amplifier Schematic Diagram" for  the Amplifier schematic
diagram and section 4.1.3 for the Output Lowpass Filter component layout and schematic diagram.

Type:

VT-3 series VHF Amplifier module

Family:

VT-3A130

Frequency Range:

118.0 MHz to 138.0 MHz

RF Power Output:

1.0 - 4.0 Watts adjustable (carrier only)

RF Power Input

Nominal level from -5 dBm to +5 dBm

System Impedance:

50 

Ω

Spurious and Harmonics Emissions:

More than 90 dB below carrier

Modulation:

6K00A3 (Amplitude Modulation)

Transmitted Noise

More than 45 dBc below carrier

Audio Response:

Flat audio; +1/-3 dB: 300 Hz - 3 kHz

Audio Distortion:

Less than 3% -40˚C to +60˚C at 30% modulation

Less than 5% -40˚C to +60˚C at 90% modulation

Load VSWR tolerance:

Z load = 20:1:

Operating Voltage:

+13.8 Vdc Nominal (range +10 to +17 Vdc),
+9.5 Vdc Regulated.

Active Current:

+13.8 Vdc supply less than 1.5 A at Pout=4

Standby Current:

Typically less than 4 mA