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Loggings => HF Mystery Signals => Topic started by: radioreddz on July 24, 2016, 0106 UTC

Title: Intimated tones 7080am
Post by: radioreddz on July 24, 2016, 0106 UTC

Is anyone listing that can tune to frequency 7080 am and identify these intermittent tones at 01:06 I have heard them on other frequencies as well.

Title: Re: Intimated tones 7080am
Post by: Token on July 24, 2016, 0423 UTC

Without a recording or at least a screen shot the best anyone can do is a WAG.

However, 7076 kHz USB is where you find the JT65 mode in use, so I would bet that is what you have, hams using the JT65 weak signal mode.

T!

Title: Re: Intimated tones 7080am
Post by: Josh on July 24, 2016, 1907 UTC

A few kc above the jt65ers on any given HAM band you'll also find jt9 ops. This is a similar mfsk signal to jt65 but the tones dwell longer on each shift.

Title: Re: Intimated tones 7080am
Post by: Token on July 25, 2016, 0012 UTC

Quote from: Josh on July 24, 2016, 1907 UTC

A few kc above the jt65ers on any given HAM band you'll also find jt9 ops. This is a similar mfsk signal to jt65 but the tones dwell longer on each shift.

True, but because JT9 uses fewer, and much smaller, steps, many people don't even hear the changes unless they listen closely.  Were the JT65 steps are normally very noticeable.

Later I will put up a video of both JT65 and JT9, for exemplars.

(edit)  I have uploaded a video of JT65 and JT9 on 40 meters.  The first three minutes are correctly tuned in USB mode for the JT65 (first 2 minutes) and then JT9 (third minute) signals.  Minutes 4 and 5 are tuned in AM mode.

https://www.youtube.com/watch?v=XDlKl_GTPKU

radioredzz, does this sound like what you hear?

T!