RX Audite – SDR splitter/switch with protections

This is very powerful device combines TRX switch, RX splitter, RF limiter protection for both RX outputs, INBAND RX antenna input and optional RX preamplifier. You can share your main TX/RX ANT to two RX with RF power limiter protection.

This is ideal solution for Spectrum Panadapter, WebSDR or Skimmer Server – RBN.

When the controller is OFF then main TX/RX antenna goes to the SDR RX output – with 10 mW RF limiter protection. You can switch ON preamplifier even you left controller OFF by the POWER switch. When the controller is ON, Main TX/RX antenna is shared between TRX and SDR outputs. During TXing, the SDR RX output can be connected to the internal dummy load or to the INBAND RX antenna input. You can switch the SDR RX output to the INBAND RX ANT port not only while the TRX is TXing, but by the front panel switch, it can be switched all time. Optional HIGH IP3 internal preamplifier can be used for insertion loss compensation. Additional gain is variable, up to 14 dB.

Main functions:

Main TX/RX ANT splitter to two RX
RX RF limiter protections for both RX outputs
Isolated SDR RX output + Common-Mode filter
HPF (> 100kHz), high voltage and current protection at both RX outputs
INBAND RX ANT input – works only for SDR output
TX-RX switch controlled by the PTT
Designed for 2nd RX, WEB-SDR, SKIMMER or Panadapter
Controller OFF = TX/RX ANT port to SDR RX out via RF limiter protections – Skimmer/web-SDR
Controller ON = TX/RX ANT port splitted to TRX and SDR RX out via RF limiter protections
TRX TX to main TX/RX ANT = SDR RX out to dummy load or INBAND RX ANT input via RF limiter protections
Front panel Switch – SDR RX output to INBAND RX ANT all time
Preamplifier (optional): insertion loss compensation, up to 14 dB of additional gain
Preamplifier could be ON for SDR even controller is OFF (both by the front panel switches)
Very high isolation when TRX TX and SDR to INBAND 100 dB @ 14 MHz and 80 dB @ 50 MHz

One black box but many different parts inside:

TX / RX switch controlled by PTT signal
PTT splitter (IN/OUT) in sniffer mode (IN directly to OUT) or output PTT FET switch
2-way RX splitter with low loss
2 x RF limiter RX protections – the best on the market
RX switch for INBAND RX antenna (only for SDR output)
Both antennas with HPF > 100 kHz
RX preamplifier (high IP3, 18 dB gain) with variable ATT – OPTIONAL
RX lines with High Voltage protections > 60 V AC
RX lines with SuperFuse current protections > 100 mA
Very high isolation TX to SDR, between RX ports, INBAND RX and TX/RX ANT port

Parameters:

Supply voltage DC + 12 to 14 V (13,8 V recommended)
Supply current DC max. 0,7 A with preamp
Very high isolation when TRX TX and SDR to INBAND 100 dB @ 14 MHz and 80 dB @ 50 MHz
PTT IN compatible with 5V logic or higher, TX = GND
PTT OUT sniffer (IN=OUT) or output FET (max. 35V DC and 0,5 A)
Default configuration SDR to INBAND RX ant input while TRX TX
Optional Preamp preset to insertion loss + 6 dB (total gain abt 10 dB)
Low insertion loss see measurements picture

RF limiters:

Limiter for RF signal to + 13 dBm = 20 mW (could be + 17 dBm) @ 50 Ohm
Current SuperFuse – the only at market
Can survive high input power (current) for long time
The soft clipping reduces the IMD products of a classic hard diode clip limiter

Internal Preamplifier module: (OPTION / version with preamp)

High IP3 preamplifier module with 18 dB gain
With 2SC5551 transistor
Real OIP3 is +34 dBm
Preset to 40 mA @ 13,8 V
Low Noise Figure (NF) < 2 dB (60 mA 50 MHz)
Variable gain by output ATT
Preset to 10 dB for TX/RX ANT to both RX outputs = insertion loss + abt. 6 dB (1S) of gain
Bypass relays
Could be switched ON even the controller has got power switch OFF – preamp for SDR output.

https://remoteqth.com/