Today I wanted to post about a new SDR project called “Backpack SDR” that’s taking shape. Since August, Keith Myles, VE3IFT has been sharing pictures of his Backpack SDR transceiver project on the Amateur QRP Radio group on Facebook:
What is the Backpack SDR?
The Backpack SDR is an HF transceiver project that is based on the Teensy 4.0 or 4.1 MCU. It uses as many off-the-shelf parts as it can in order to keep the build simple and also keep costs down. It’s not a budget build, per se, but the basic mono-band Backpack SDR can be built for under $200.
When Keith shared the pictures above, they immediately generated interest, not because the transceiver is particularly a new concept, but because of the way it’s designed. While many projects are monolithic in that the technology is all specific to the project, Keith has designed his Backpack SDR project to make use of modules. In fact, the name “Backpack” refers to its construction, not portability!
Backpack SDR: How hard to build?
With some basic soldering skills, some wiring, and some firmware (as easy as an Arduino sketch, as far as I can tell) an SDR is born. The Receiver module, filters, and 10W PA all come from QRP Labs (see links below) and the rest can be had on either Amazon, Banggood.com, or eBay.
How to Learn More
Are you interested in learning more? First, join the “Keiths_SDR” Facebook group. Instructions, firmware, and assistance are available there. If it looks like something you’d like to do, then the majority (if not all) of the parts are listed below from the three vendors previously mentioned:
|Part||Amazon Link (or Other)||Bangood Link||Ebay Link|
200mm x 175mm x 70mm
|Teensy 4.0 (Mono Band)||Amazon|
|Teensy 4.1 (If you're going multi-band)||Amazon|
|3.5" LCD Screen Module TFT 3.5inch SPI Serial 480 x 320 ILI9488||Amazon||Ebay|
|Teensy Audio Interface Board||Amazon||Ebay|
|QRP Labs Modules||Receiver Module|
10W HF Linear Amplifier
Ultimate LPF Switch (can be used for BPF too)
Band Pass Filter
Low Pass Filter
|Si5351 Breakout board or module||QRP Labs Si5351 Synth Module|
|Pin Header Kit||Amazon||Bangood||Ebay|
|Right Angle 2x40 Pin Headers||Amazon||Ebay|
|Stackable Shield Header Kit||Amazon|
|Dupont Wire Kit||Amazon||Bangood||Ebay|
|Photoelectric Rotary Encoder||Amazon||Bangood|
|Mechanical Rotary Encoder||Amazon||Bangood|