Topband: Digital mode spurious issues

[Jim Brown]

You're both right -- it is either JT65 or JT9. WSJT software, based on 
protocols developed by K1JT, will decode both modes. Another software 
package called JT65-HF will decode only JT65.

And yes, the trash Tom was hearing was either overdriven audio or a 
crummy radio or both.  Some of the newer hams using these modes are also 
using pretty crummy radios -- all-banders in the $900 price range. OTOH, 
most are running flea power -- 20W is QRO for this crowd.

I've done a fair amount of JT65, mostly on 6M and 160M, using my K3. 
I've also used other K1JT modes designed for meteor scatter (FSK441) and 
ionospheric scatter (SCAT). JT9 is Joe's latest and greatest protocol, 
requiring a fraction of the bandwidth of JT65.

73, Jim K9YC

On 12/30/2013 10:30 AM, Mike Waters wrote:
> I believe the mode that operates at 1873-1838 is JT65, and WSJT is needed
> to decode it. I never tried it. It was developed by K1JT for weak-signal
> and EME work.
> http://www.physics.princeton.edu/pulsar/K1JT/wsjt.html
>
> A common scenario with digital modes is that the audio into the mic input
> is too high, causing unwanted spurs.