The intent of his section is to document my experience with Software Defined Radio (SDR). I run only Linux on my computers, so my use of Software Defined Radio – and my observations about it – will be in that general context. SDR has become my area of strongest interest in Amateur Radio.

I possess SDR devices that connect to a computer via USB.

• Several RTL-SDR dongles. My experience with them so far is documented here, and in notes for the Linux User Net.

I have owned three SDR transceivers (described below). My current rig is the FlexRadio 6600. For my experience with it, SEE HERE.

Icom IC-7300. The IC-7300 was my first HF rig. It is a direct-sampling SDR HF transciever. Though a true SDR internally, it's designed to operate pretty much the same as an analog set, controlled with the customary knobs and buttons. The touch-screen interface for the menu system is its primary visual digital distinction. I particularly like the filters, which are extremely adjustable and are automated nicely. I also like the fact that it has a USB port for direct connection to a computer, without having to to use a special adapter or cable. Also, the USB port makes two connections, one of which is a sound card that can be used by the computer for digital mode operation – though I haven't yet tried it.

This is a fine radio, and it has served me well. However, from the viewpoint of working dirctly with SDR itself, it is very limited. That led me to look for equipment that would give me greater opportunity for experimenting with software defined radio.

In August, 2019, I purchased a Flex-6600 and a Maestro Control Console. In contrast to the closed-box character of the IC-7300, Flex has designed a system that operates over a computer network. The 6600 is a direct-conversion SDR transceiver, with a built-in radio server that sits behind an Ethernet port. The only user control on the box is the power switch; all other control is accomplished through software that communicates with the server via TCP/IP through the Ethernet port.

Late in 2021, I decided to switch to a SunSDR2 DX, primarily owing to the fact that its ExpertSDR software runs natively on Linux, whereas SmartSDR for the Flex is Windows-only. I have subsequently switched back to it.

In February 2021, a SunSDR2 DX from Expert Electronics arrived at my door. I used it for a year and still have it, though it's not in use presently (May 2022). I have switched back to the Flex 6600, for reasons detailed HERE.