SO2R Box

The SO2R Box (plus) allows an operator to listen and transmit on two (or four) radios, transmitting on one and listening on another, or listening on two radios at the same time. It has switching for headphones and microphone, a built-in keyer, and auxiliary LPT-style outputs. It connects to the computer through a USB interface.

It works with major contest logging software including N1MM Logger, Win-Test, and WriteLog.

This is what it looks like.

The unit is a kit. There is one PC board. All of the components are soldered onto it.  The board has three surface-mount parts which we solder before we ship them.

This is prototype #3 wired for SO2R operation.
A production board is almost identical.

YCCC makes these available as part of a group purchase.  We collect orders and money and then order the parts. The parts include the PC board and the box - everything needed except for some solder. It also includes DIN plugs and a power plug.

We charge essentially the cost of parts and shipping.  If there is any left over we donate it to an ARRL scholarship fund. We also donated some towards generators for Puerto Rico in 2017.

Project Status

We are not currently planning another group purchase.  For more information contact Dennis, W1UE, at .

V1.12.1 software and V1.6 firmware are now available.  This provides the ability to listen to more than two radios at once should a logging program support this in the future.  V1.12.1 has a couple small changes to the keyer code which fixes an occasional problem where a message with speed changes will go back to the original speed while playing.

The construction information is available on the downloads page.

N1MM Logger V9.8.4 supports the SO2R Box

N1MM Logger Plus supports the SO2R Box

WriteLog V10.73 supports the SO2R Box

Win-Test V4.4 supports the SO2R Box.

TR Log Linux supports the SO2R Box

DXLabs Suite supports the SO2R Box. supports the SO2R Box.

If any other club would like to organize a group purchase we will supply the necessary files for the box and the board and we can help program the microprocessors.

Project Staff

Paul, K1XM is the hardware and firmware designer

Bruce, WW1M, is the PC board designer.

Ken, WO1N contributed to the ESD design.

Jose, N4BAA is the box designer.

Dennis, W1UE handles parts and order fulfillment.

Software and Documentation

Software, firmware, and documentation are available on the downloads page.