Re: LF: RE: 74.322 kHz Op-64 from Bob and Dex

["Markus Vester" <markusvester@aol.com>]

Terry,

 

good point: If you retune your RX from 72.7 to 72.8, the FFT center frequency in SpecLab needs to be 100 Hz lower, ie. changed from 1622 to 1522 Hz. Opds.ini entries can stay the same.

 

Best 73,

Markus

 

From: Terry GW0EZY

Sent: Sunday, February 09, 2014 9:38 PM

To: rsgb_lf_group@blacksheep.org

Subject: LF: RE: 74.322 kHz Op-64 from Bob and Dex

Markus

 

Thanks for opds settings.

 

Sorry ? I have to ask for explanation ?Opera software users should tune to 72.8 kHz dial?

 

Should opds users also set 72.8 dial? If not, then can?t run Opera and opds in parallel from same Rx.

 

If so, do I also change the additional SL settings (that worked FB last night for OP 16):

CF=1622

RF Offset 72.7  to 72.8

 

73 Terry

 

From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of Markus Vester
Sent: 09 February 2014 19:46
To: rsgb_lf_group@blacksheep.org
Subject: LF: 74.322 kHz Op-64 from Bob and Dex

 

Bob and Dex intend to transmit Opera-64 tonight, WG4XRS on 74.3213 and WG5XRS on 74.3229 kHz.

 

Opera software users should tune to 72.8 kHz dial to bring the signals inside the prescribed Op-64 passband.

 

Opds users can start out from Op-16 settings, but reduce FFT bin size by a factor of four from 0.954 mHz to 0.238 mHz.

 

Example settings for SpecLab with opds-64:

 Audio samplerate 12 kHz, 

 FFT decimation divisor 768,

 FFT length 65536,

 scroll interval: 20 minutes,

 number of exported bins: 32768,

 untick use INTEGER numbers only.

 

Example parameters for opds.ini:

 opspeed=64
 spotdelay=58 ' seconds
 fc=74322 ' center frequency (Hz)
 sr=12000.86  'enter your calibrated samplerate (Hz)
 dec=50331648   '768*64k

 

73 and good luck,

Markus (DF6NM)