Modulation: Sound Card Digital Modes on HF SSB
Speaker: Barry Feierman, K3EUI
Sound card modes: How they look and sound. What can a sound card do that a human voice cannot do in terms of passing information on a radio signal?
Barry will discuss the concept of modulating a 145 MHz RF wave with a 1.5 kHz sound wave. He will transmit a signal first on AM, then on SSB, and finally on FM. Using an SDRPlay receiver with a spectrum analyzer set to 145 MHz, he will display the RF spectrum of these signals.
Barry will demonstrate a variety of popular sound card digital modes, including CW, PSK31, RTTY, Olivia, MFSK, and THOR. Using an SSB transmitter, he will share with NY ops who have an 80m SSB radio and antenna what these modes sound like (assuming propagation from Philly to Schenectady on 80m NVIS).
He will use the internet sound as a backup. Popular apps like FLDIGI and Winlink use these sounds created in a sound card to produce “modes” that transfer information much faster than is possible with a human voice on a phone link. Rates as fast as thousands of bits per second on HF SSB is possible using modern sound cards (getting beyond the present 300 baud speed limit of one carrier on HF bands in the USA).
About our speaker:
Barry was first licensed KN3EUI in 1958 when he was 13 years old and quickly fell in love with CW and 40 meters. After advancing to General one year later and operating on 10m, he was working the world on HF AM and CW. His rig was a Heathkit DX100, so no SSB modes.
Barry’s professional training is in Astrophysics, having worked and studied at Swarthmore College Sproul Observatory, and then further graduate work at Kitt Peak and the University of Arizona. He also worked summers at the Royal Greenwich Observatory (England) and the U.S.Naval Observatory in Washington DC, and then at Flagstaff, Arizona. He spent a sabbatical year and a few summers at Lowell Observatory (Flagstaff, AZ) where he got to have lunch with the man who discovered Pluto at Lowell.
Barry’s teaching career began at Westtown School in West Chester (PA) in 1970, where he taught high school physics, astronomy, and electronics for over forty years. He then spent a year teaching physics at university (West Chester) and Bryn Mawr College.
Barry’s interests in ham radio now include the sound card digital modes, the Nano VNA as a test instrument, and modulation methods on HF SSB and VHF FM using the SDRplay and RSP Spectrum software. He is the net manager of the PaNBEMS net every Sunday morning at 0730 on 3583.0 kHz. He is also active in local county EMCOMM work via ARES/RACES.
Barry is an extra class licensee, and lives in West Chester, PA.
Note: The meeting location is 309 Alplaus Ave, Alplaus, NY, and the building is at the corner of Alplaus Avenue and Bruce Drive. Please park in the paved lot adjacent to this building. Do not park in the restricted area in front of the building that houses the fire trucks. We will meet in the Multi- purpose Room (entrance is on the North side of this building).