IQ32 QRP SDR Transceiver
Several years ago I purchased a SDR QRP transceiver, the RS-HFIQ, from HobbyPCB. It is a 5 watt SDR radio that covered 80-10 meters. The radio required a PC, a Sound Card, and a couple of USB ports to function. Once assembled and hooked to the PC the system was fully functional on SSB but lacked a CW mode without using a external I/Q keyer. The SDR software used was HDSDR, not one of my favorites. There were many cables required to hook up the SDR and although it worked very well it was cumbersome to use especially on CW where the I/Q keyer needed to be inserted between the Sound Card and the radio. So after the initial assembly and startup, the fun wore off very quickly and the RS-HFIQ wound up in a drawer for quite a while. I was always very impressed with the performance of the RS-HFIQ transceiver, especially the receiver. However, it was cumbersome to hook up all the cables to my notebook computer. One of my main uses for a QRP radio is using it as a portable station in the field. To use it as a field radio would be difficult because of carrying a notebook, keyer, and cables to hook the radio up.
Earlier this year HobbyPCB came out with a kit to make the RS-HFIQ SDR a stand alone QRP transceiver, the IQ32. Details from the HobbyPCB website are here:
https://www.hobbypcb.com/index.php/products/hf-radio/iq32-detail
I quickly ordered the IQ32 upgrade kit, dug the RS-HFIQ out of a drawer and in a few hours I had a very nice, small, stand alone SDR QRP radio.
At 6.5″ X 4″ X 3″ the IQ32 is a compact and light weight transceiver, with only two knobs and a touch screen to handle human interface functions. It is fully functional on SSB, CW, and even has built in provisions for PSK-31 transmit and receive. It uses band switched mutli-pole LC passband filters to provide excellent receiver performance and eliminate harmonics from the transmitted signal. This is by no means your typical “dongle” SDR receiver performance, it is an excellent receiver with good sensitivity and select-able receiver bandwidth filters for SSB and CW. The 5 watt transmitter output will provide hours of fun contacts on its own, but pair it with the HobbyPCB Hardrock 50 compact 50 watt linear amplifier and you are now only 3 DB down from your 100 watt desktop transceiver! Using the Hardrock 50 with the IQ32 is easy. A single cable between the IQ32 and the linear sends band data and PTT keying to the Hardrock so the amplifier tracks the band changes on the IQ32. Very nice!
I have made a number of CW contacts all over the eastern half of the US with 5 watts and a dipole. I made a few contacts on SSB too, just to make sure it worked and it does work quite well. The little rig performs great with good filters, good AGC action, and a built in CW keyer with adjustable speed, weight, and semi break-in functions. You can also select a straight key mode that can be used with either a straight key or an external keyer. There is a frequency split mode for CW that allows for a separate send and receive frequency. If someone comes back to you on a slightly different frequency you can leave the TX frequency where it is and tune the RX frequency. The split feature is not found on typical QRP radios.
Another very cool feature of the IQ32 is that it will send and receive PSK-31 without the use of a external computer. All that is required is a keyboard which plugs directly into the IQ32. The received signal is decoded and displayed on the touch screen. Below is a short video of the PSK-31 receive mode. The keyboard is also used for editing the 15 memory tags and to send CW.
One of the things I like best about SDR radios is that new features and functions can be implemented without hardware changes by updating the software. In October a new firmware release came out, version 1.100, that added many features to the IQ32. Chris, VE7XH, has worked diligently on this new firmware release and has done an excellent job. He put together a short video demonstrating the new features.
So, I think you will like this compact little SDR for either operating from home or portable in the field. Either way the IQ32 is a top notch performer!
DE N4RFC – Bob
The RS-HFIQ required an IQ Keyer, which I’m guessing means two audio channels, both at something like 750 Hz but offset 90 degrees? Does this one use an external keyer or just a paddle input (stereo plug)?
The I/Q keyer generated two sine waves shifted 90 degrees in phase. The IQ32 has an internal keyer and CW generator so all you need is a paddle with a stereo plug.
The keyer can be set up for Iambic A or B, has adjustable weight or can be turned off for a straight key or external keyer. The break in delay is proportional to the keyer speed, as you increase the keyer speed the drop to RX delay is decreased. It works very well.