Weak Signal Modes

Andrew Rohne AC8JOFebruary 9, 2012

Three Part Presentation

JT65WSPRQRSS

JT65 and WSPR

Both by Joe Taylor, PhD K1JTAstrophysicist at PrincetonNobel Prize in Physics 1993

Time sync CRITICALLong TX and RX sequencesWeak signal - use low power

JT65

Originally for EME on HF and VHFThree Submodes

JT65A ~> HF and 6mJT65B ~> 2m and 70cmJT65C ~> 23cm

Short, to-the-point QSOs

Less sensitive More resistant to libration fading & frequency drift

JT65

13 Characters onlyNot a ragchew mode! Allows for signal report and 73

only53 second TX/RX SequencesHF Skywave ~> JT65-HF

JT65-HF Software

JT65 QSO (with N1FIY)

N1FIY AC8JO EM79

N1FIY AC8JO R-09

N1FIY AC8JO 73

JT65 post-QSO

JT65 QSO

CQ K1JT FN20K1JT W6DTW CM97W6DTW K1JT -18K1JT W6DTW R-16W6DTW K1JT RRRK1JT W6DTW 73W6DTW K1JT 73

(QSO Stolen from NW7US.US/jt65a.html)

WSPR

Weak Signal Propagation ReporterNot a QSO ModeTransmits call+grid2 Min TX/RX SequencesClock important!WSPRNet.org

WSPR Software

WSPRNet.org (Spotting)

Spotting Map

Spotted!

206 mi per watt

Spotted Map

QRSS

Super Slow CW“Normal” or FSKCWHellschreiber has been used

Not a QSO mode

Software

QuickTime™ and a decompressor

are needed to see this picture.

Website - “Pensacola Snapper”

Conclusion

JT-65WSPRQRSS

Andrew Rohne AC8JOwww.ac8jo.us