File:QRS "Red Top" Super Detector-Type Radio Tube By QRS Music Co., Circa 1920s (8723311651).jpg - Wikimedia Commons
QRSS Plus
LA3ZA Radio & Electronics: Ultimate QRSS kits
Midland Emergency Weather Alert Radio - Bliffert Lumber and Hardware
Amazon.com: JR Radio JRPS02419 ELG01 QRS Tail Servo: 500-550 Class : Toys & Games
Crossing the pond with 100 milliwatts – NYC Resistor
GitHub - swharden/QRSS-VD: QRSS Viewer for Python 2
The Sproutie “SPT” Beacon – A Legal, Unlicensed HiFER Beacon – Dave Richards AA7EE
Crossing the pond with 100 milliwatts – NYC Resistor
QRSS – enjoying life in the radio slow lane
QRSS - DJ9EV
EI7GL....A diary of amateur radio activity: QRSS signals heard on 80 metres - 1st Apr 2019
GitHub - jaesparza/radio-beacon: A multimode radio beacon for QRSS (FSK-CW, CW) and WSPR. Implemented using AD9850 and STM32duino. Repository hosting schematics, software and other implementation notes.
QRSS RECEIVER FOR TWO BANDS
QRSS CW—SENDING SLOW CONTINUOUS WAVE: PART 1
Build your own QRSS transmitter - Resource Detail - The DXZone.com