[A-DX] VOA Radiogram, 4-5 April 2015, 8PSK125R with pilot tone

[Roger]

Am 03.04.2015 um 05:41 schrieb VOA Radiogram:
> Last week's test of the 8PSK FEC modes was interesting. In general, 
> the 8PSK FEC modes did not perform as well as well as the MFSK modes. 
> However, Richard in New Brunswick and I, using a receiver in Nova 
> Scotia, had 100% copy of all the modes, including 8PSKR250F at 635 
> wpm! This mode might be useful for high-speed data transmission, 
> including formatted web pages, over distances of 1500 km or less, 
> especially when propagation is stable.
>
> This weekend we will do one more test of 8PSK125F. This will actually 
> be two transmissions, one without the pilot tone, and one with the 
> pilot tone. You do not need to make any adjustments to detect the 
> pilot tone, other than to have the Fldigi RxID on (green). "The RsID 
> signal will both determine the mode and the mode center frequency (to 
> the nearest 2.6 Hz). A finer resolution of the mode center frequency 
> can be made using the optional pilot carrier," according to the Fldigi 
> Users Manual <http://www.w1hkj.com/FldigiHelp-3.22/psk_page.html>.


If a bandwidth of 2.5 kHz or more are available, then the usage of 
narrow modes is less reasonable.
I'm still hoping for a robust fast mode of 2x or 3x MFSK-32.
When decoding of the backscattered signals from KBC via Nauen (European 
night/86 miles/skip zone for me) MFSK64 is at the limit of its 
possibilities.
For the text-decoding   the error correction helps.

http://www.rhci-online.net/radiogram/VoA_Radiogram_2015-04-04.htm


roger