Hi Mike and Bill

 

As an interim solution you can produces single tones  in QRA by typing in
"@1000" for T = tune, "@1250" for please send messages, "@1500"  for RRR and
"@1750" for 73 and reading them from the waterfall as you do for JT4.  These
are around 3 to 5 dB more sensitive than gaining sync on QRA so well worth
using to complete a marginal QSO.  But at this stage have not been
implemented on QRA in the way they are done on JT4 and do not show up as the
transmitted message in QRA even though they are being transmitted.  Joe is
of the opinion that even a longer Costas array will not be as sensitive as
single tones.

 

Single tones are too wide to use at HF where you try to minimise the
bandwidth and should normally be used only with Doppler correction for EME
although you probably get away without Doppler correction at VHF.

 

73 Rex VK7MO

 

 

From: Bill Somerville [mailto:[email protected]] 
Sent: Sunday, 28 August 2016 12:42 AM
To: [email protected]
Subject: Re: [wsjt-devel] EME Short Tones

 

On 27/08/2016 15:12, Black Michael wrote:

Is QRA mode supposed to allow short tones too?  No Sh box on that one.

Hi Mike,

I don't believe short codes have been implemented for QRA64 mode, IIRC there
has been some discussion on using an extended length Costas array (the same
modulation scheme  that is used for the embedded sync transmissions).
Another option might be to uses continuous sine tones like JT4 uses but it
may turn out that QRA64 is so sensitive that they might not be visible with
the weakest detectable, decodable signals.

73
Bill
G4WJS.

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