2025-P-041-U | SVXLink Analog HotSPOT2 70cm 100mW UHF PCB

Available as a complete product with CE certification: https://shop.rf.guru/products/2025-ce-041-u

Warning: Only the complete product carries CE certification; PCBs do not!

Experience the power of the SVXLink Analog Hotspot2, a cutting-edge HAT designed exclusively for the Raspberry Pi Zero.

Packed with a formidable UHF 70 cm 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 hotspot.

What's more, with the combination of a remote SVXLink with AnalogBridge (DVSwitch), you gain access to digital networks, including the Brandmeister and OpenDMR network, unleashing a world of limitless possibilities. 

 Datasheet

• Raspberry PI Pin compatible
• PCB ENIG (Electroless Nickel Immersion Gold)
• UHF 70cm band frequency: 400~480 MHz
• Tx and Rx frequency, Tx and Rx CTCSS, CDCSS can be set separately.
• Band width 12.5KHz / 25 KHz
• Output power 20dBm / 100mW
• RX Sensitivity：-118 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 Zero W

• Receive modus 220mA
• Transmit modus 370mA

PCB Components

While we offer the option to purchase pre-assembled devices for your convenience, pcb assembly is fairly easy (only 3 parts to solder) !

• 1 x Rf.Guru PCB
• 1 x 40 Pin Header
• 1 x SMA socket
• 1 x UHF SA818S Radio module

Assembly / soldering

Begin by soldering the RF chip, aligning it according to the layout. Next, solder the 40-pin header, and finally, solder the SMA connector.

Software

https://github.com/Guru-RF/SVXSpot?tab=readme-ov-file#svxlink-bookworm-image

https://github.com/Guru-RF/SVXSpot

Measurements

All measurements were conducted using a calibrated VNA and a calibrated 30dB attenuator. The worst harmonic observed is the third, measured at -86.23 dBc, which is significantly better than the requirements of the CE-RED directive for devices under 30dBm output power. According to the directive, spurious emissions must typically be at least 43 dB below the transmitter power for frequencies below 30 MHz, and 60 dB below for those above 30 MHz. Our device comfortably exceeds these limits, even surpassing the stricter standards for high-power devices. 😉

The spectrum analysis confirms similarly excellent performance for spurious emissions, with no significant unwanted emissions detected. Additionally, the device transmits cleanly within the 12.5kHz channel bandwidth, ensuring precise and reliable operation.

When compared to leading brands such as Kenwood, Icom, and Yaesu, our device holds its own:

• Our measured spurious emission levels of -86.23 dBc clearly demonstrate superior spectral purity.

This level of performance ensures compliance with international standards and places our device in the same league as the most respected brands in the market.

Spectrum

Harmonics

Channel Power