What is it?

This is a high-performance SDR TX/RX Antenna Sharing Switch Box designed for amateur radio enthusiasts, RF engineers, and makers who work with Software Defined Radios. It enables seamless switching between transmit and receive paths using RF sensing or PTT control. Designed with DIY-friendly usability, this compact yet powerful switch allows for efficient antenna sharing between your transceiver and receiver setups without manual intervention.

Compatible with most SDR transceivers and standalone receivers operating from DC to 160MHz, this unit supports up to 100W of transmit power with low insertion loss and high isolation. Whether you're building a portable field station or a compact home shack, this RF antenna switch delivers performance and convenience.

Why did you make it?

In the DIY and maker space, SDR users often need a reliable, automatic way to switch between transmission and reception while sharing a single antenna. Most available solutions are bulky, complex to wire, or lack compatibility with standard SMA/BNC connections. We designed this TR Switch Box to solve those problems – offering RF-sensed switching in a durable, aluminum-alloy enclosure that’s easy to integrate into any RF or SDR setup. We wanted something plug-and-play, high quality, and tailored for ham operators, shortwave listeners, and field deployers who want to simplify their gear without compromising performance.

What makes it special?

Wide Frequency Range: Operates from DC to 160MHz – ideal for HF, VHF, and some UHF applications.

High Power Handling: Supports up to 100W TX power, suitable for most ham radio and SDR transmitters.

RF Sensing + PTT Control: Automatically switches with RF presence (<20ms ON, <190ms OFF), or manually via PTT signal.

Low Insertion Loss: Typical 0.2dB loss @ 144MHz, maintaining signal integrity.

Excellent Isolation: Receive path isolation >38dB, prevents damage or interference.

Gas Discharge Protection: Protects circuitry and connected equipment from surges.

High Build Quality: CNC-machined aluminum alloy housing ensures durability, RF shielding, and lightweight portability.

Complete Kit: Includes SMA cables, power supply, and BNC adapter for immediate integration.

DIY-Friendly: Compact and easy to mount or embed in custom enclosures or radio kits.

Product Specifications:

Impedance: 50Ω

Frequency Range: DC – 160MHz

Max Transmit Power: 100W

RF Sense Response: ON < 20ms / Release < 190ms

Insertion Loss: <0.3dB @ 144MHz (typical 0.2dB)

Receive Isolation: >38dB @ 144MHz (typical 40dB)

Protection: Gas discharge built-in

Power Input: 12V 2A (US plug included)

Dimensions: 125 x 112 x 51mm (excluding connectors)

Net Weight: 430g

Compatibility

This TR switch is compatible with:

SDR transceivers like HackRF, Hermes-Lite, FlexRadio, SunSDR, and more

Receive-only SDRs like RTL-SDR, SDRplay, Airspy (when used in duplex or diversity setups)

Analog HF/VHF radios needing TX/RX switching

Ham radio stations using single antenna setups

Raspberry Pi or Jetson Nano-based SDR experiments (with appropriate HATs)

Antenna analyzers and remote switching nodes

Design Philosophy

Every SDR and ham radio project should have a reliable, noise-free switching mechanism – without needing a rack full of relays or heavy-duty switching matrices. This TR switch box simplifies your build, offering automatic RF-sensed switching that’s compact, safe, and efficient. Whether you’re bench-testing a transceiver build, deploying a field radio kit, or just keeping your shack tidy, this switch adds real value. Its compact form factor means it won’t clutter your workspace. Its sturdy aluminum casing ensures it can travel with your gear safely. And its clean RF performance means fewer headaches when you're trying to debug or fine-tune your signal path.

Note

Always verify antenna SWR before transmission to prevent device damage.

Not suitable for frequencies above 160MHz.

Avoid transmitting without a load connected.

This product is ideal for makers, field operators, and experimenters looking for simplicity, performance, and reliability in one powerful SDR antenna switch solution.