URX PCB layout (preliminary) (click to enlarge)out of production
URX PCB layout (preliminary) (click to enlarge)
This VHF receiver can be controlled by a SHACKBUS interface
Typical application: IF receiver to be used with a UHF / SHF / EHF converter with a IF of 71.0, 110.0, 137, 144-148 MHz etc.
Supply: 12 volt (11 to 16 volt), approx. 200 mA
Dimensions: 88.6 x 109.2 mm, height approx. 25 mm
Frequency control: Programmable via SHACKBUS interface in 10 kHz steps. 16 frequencies can be stored in EEPROM and selected by 4 switches / jumpers for stand-alone operation without controller.
IF-Bandwidth: 4 filters can be selected via SHACKBUS commands:
30kHz (9600/19200 baud FSK)
60kHz (38400 baud FSK)
120kHz (76800 baud FSK)
300kHz (153600 baud FSK).
Data output: Two separate outputs for narrow (9600 / 19200 baud and FM audio) and wide (38400+ baud).
Audio output: 0.3 watt speaker output with on-board volume and squelch control.
IF output: 10.700 MHz buffered output for PSK or SSB demodulators
Signal strength display: the signal strength can be displayed in dBm via SHACKBUS (calibrated with adjustable offset for additional converter gain). An analog meter can be connected.
Center meter: the frequency offset (e.g. doppler shift) can be read out vie SHACKBUS, an analog meter can be connected. This output can also be used to control the AFC input of the PLL oscilator of the converter.
Receiver circuit description: The input signal is amplified by an amplifier with high interception point for excellent large signal characteristics. The local oscillator oscillates 10.700 MHz above the input frequency and is PLL-controlled (10 kHz steps). The 10.7 MHz IF signal passes two separate filters. There are 4 different pairs filters installed, switched by a SHACKBUS command. For wide band FM the 10.7 MHz is demodulated using a Q-multiplier for the quadrature circuit for better signal at 38400 baud FSK. Narrow band FM (for FM-audio, 9600 baud and 19200 baud FSK) is converted to 455 kHz and demodulated in a circuit with high linearity and flat frequency and phase response for best FSK data reception.
Terminals: RF input, data (narrow) output, data (wide) output, audio output, AFC ( center meter) output, RSSI output, SHACKBUS interface, 10.7 MHz linear IF output, 12 volt supply terminals.
URX will be available in summer 2001
PLL Programmable precision PLL for 100 to 1300 MHz. Temperature
compensated / 50 Hz resolution / AFC, RIT, Fine tuning with external DC
voltage, FM modulation (up to 153 kbaud FSK), 5 mW output power.
F70, F23, F13: RF front-end (Converter, Mixer) for 70cm (435MHz), 23cm (1250MHz) and
13cm (2450 MHz). To be used with the PLL oscillator and the URX-receiver as 71
MHz IF amplifier and demodulator.
BUS Info / manual of the BUS RS232 / SHACKBUS converter board