2023-P-141-V | SVXLink Analog FM Transceiver HAT 2m VHF 1.3W
2023-P-141-V | SVXLink Analog FM Transceiver HAT 2m VHF 1.3W
Experience the power of the Analog FM Transceiver HAT, a cutting-edge HAT designed exclusively for the Raspberry Pi Zero 2W.
This device needs more power than the Raspberry PI can provide, best combine this with our PI Zero clean power supply to enable a solid and clean 5V DC input.
Without the additional power supply the output power drops to 1W !
This device incorporates an LTTC low pass filter and complies with regulations!
Packed with a formidable VHF 2m band radio module, this versatile device is accompanied by a state-of-the-art DAC/ADC, enabling it to function flawlessly as an EchoLink/SVXLink analog simplex repeater or hotspot.
The board includes an on-board low-pass filter designed to block harmonics from reaching the antenna output. This enables seamless connection of the transceiver module to an outdoor antenna, without encountering any problems. Additionally, it provides the option to drive a PA for enhanced output power capabilities.
What's more, with the combination of a Raspberry PI Zero 2W and SVXLink with AnalogBridge (DVSwitch), you gain access to digital networks, including the Brandmeister and OpenDMR network, unleashing a world of limitless possibilities.
This module can also serve as a remote transceiver module, featuring remote speaker and microphone functionality (please note that the software for this feature is still under development).
Datasheet
- Raspberry PI Pin compatible
- PCB ENIG (Electroless Nickel Immersion Gold)
- VHF 2m band frequency: 134~174 MHz
- Tx and Rx frequency, Tx and Rx CTCSS, CDCSS can be set separately.
- Band width 12.5KHz / 25 KHz
- Output power 1.3W/31dBm
- RX Sensitivity:-124 dBm
- Adjustable RX en TX volume
- 1 ppm KDS TCXO crystal
- Wolfson WM8960 ADC/ 1W DAC 48khz
- Signal/Tone Blue LED
- TX/PTT Blue LED
Power consumption in combination with a Raspberry PI Zero2 W
- Receive modus 1.6W/120mA
- Transmit modus 5W/370mA
Kit Components
While we offer the option to purchase pre-assembled devices for your convenience, kit assembly is fairly easy (only 3 parts to solder) !
Transceiver
- 1 x RF.Guru Transceiver HAT PCB
- 1 x 40 Pin Header
- 1 x SMA socket
- 1 x VHF SA868 Radio module
Measurements
Due to the added low pass filter, the board meets regulations (ETSI EN 301 783) and can be used on an outdoor antenna ! The spurious emissions are -47 dBc less then the fundamental frequency and is far more then the (43+10*LOG(1.3)) = -44dBc requirement !
Antenna
The RF 50 ohm output requires an antenna with a SWR (Standing Wave Ratio) of less than 4:1, which is considered reasonable. If you experience sound distortion, it could indicate that the antenna being used has a high SWR, leading to common-mode currents that may affect the RF chip. To test, use a 50-ohm dummy load (for UHF) and consider using a more suitable antenna. We recommend and sell antennas that work without any issues.
Enclosure
(in development)
Antenna
The Diamond SRH701 is an excellent match for our transceiver hat!
Software
https://github.com/Guru-RF/SVXSpot