User's Manual

Rev. 02
CST38 User Manual
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TECHNICAL SPECIFICATIONS
 Switchable channels : 16, preset in the 140 ÷ 250 MHz range (other upon request).
 Switching-window : 10 MHz (other upon request).
 Frequencies : microprocessor controlled PLL synthesizer circuit, with 25 kHz
minimum step [1].
         
Programming 
 Channel spacing : 25KHz standard (Other on request)
 Frequency error : < ±5 ppm, in the rated temperature range.
 Temperature range : -10 ÷ +55 °C.
 RF output power : 300 ÷ 10 mW ( 1 dB) [1].
 RF output impedance : 50 ohm (type N-F connector).
 Spurious emissions : < 2 nW.
 Transmission activation : remote PTT (Push To Talk) circuit, wired to 
jack connector.
The transmission is allowed when the central pin (hot) is
connected to external ring (ground). See Note #1 on front
page.
 Modulation : FM (peak deviation = ±5 kHz).
 Mod. audio input : transformer balanced, floating.
 Mod. audio input level : Micro / Line switchable, and externally adjustable between:
 Micro = -64 ÷ -34 dBu (0.5 ÷ 15 mV)
- Input impedance = > 2 Kohm
 Line = -22 ÷ +8 dBu (60 ÷ 1,950 mV)
- Input impedance = > 10 kohm.
 Peak-limiter : automatic, with dynamic-range > 30 dB over the level set for
the nominal modulation.
 NR system : compressor circuit with noise-gate, specially adapted to the
MicroEar receivers.
 AF bandwidth : 200 Hz ÷ 5 kHz (-3 dB).
 Distortion : < 0.5 % (0.25% typ.).
 SND/N ratio : > 80 dB (83 dB typ.), CCITT measured.
 Led indications :  Transmitter On (red LED)
 Limiter On (yellow LED).
 Powering : 10.5 ÷ 16 Vdc, 300 mA max. (negative ground).
 Dimensions : 40 x 120 x 175 mm.
 Weight : 700 g ca.
NOTE [1]: according to local regulations