On VOA Radiogram, program 49, 8-9 March 2014, the experiment will involve the audio frequency of a received MFSK32 transmission.

We hope that simple, receive-only applications (apps) are developed to decode MFSK32 on PCs and mobile devices. One requirement of MFSK is that the receiver and software be tuned to the precise frequency.

VOA Radiogram is typically transmitted on an audio frequency of 1500 Hz. The audio frequency as received tends to be a few Hz above or below 1500 Hz.

Would an MFSK32 app require an RxID to ensure that the received audio frequency is exactly correct? Or is there enough tolerance in MFSK32 that an RxID is not necessary?

VOA Radiogram, program 49, will begin with MFSK32 on a center audio frequency of 1600 Hz, with an RSID.

Just before 4:51 into the program, I will ask VOA Radiogram listeners to turn the RxID off and manually tune to an audio frequency of 1500 Hz.

Please let us know if you are able to decode the subsequent VOA News story without the assistance of the RxID.

During that VOA News story, you can turn the RxID back on.

For unattended reception, turn RxID off and set the audio frequency to 1500 Hz. You should decode everything after 4:51 into the show.

Here is the lineup for VOA Radiogram, program 49, 8-9 March 2014, all in MFSK32:

  1:37  1600 Hz: Program preview
  3:14  1600 Hz: Introduction to MFSK32 experiment
  4:51  1500 Hz: Cyber attacks on mobile devices, with image
10:33  1500 Hz: Ukraine telecommunications under attack
17:44  1500 Hz: Request for comments about shortwave, with image
20:11  1500 Hz: BBG FY 2015 budget request, with Flmsg* table
27:00  1500 Hz: Closing announcements

*Use Flmsg with Fldigi, both available from w1hkj.com.
 
Please send reception reports to radiogram@voanews.com

VOA Radiogram transmission schedule
(all days and times UTC)
Sat 0930-1000 5745 kHz
Sat 1600-1630 17860 kHz
Sun 0230-0300 5745 kHz
Sun 1930-2000 15670 kHz
All via the Edward R. Murrow transmitting station in North Carolina.

Winter SWL Fest

See you at the Winter SWL Fest, 14-15 March 2014, near Philadelphia. I’ll be there to demonstrate to decoding of text and images on VOA Radiogram. Attend one or both days. Registration at the door is welcome. Information at swlfest.com.

The Mighty KBC

The Mighty KBC, with studios in the Netherlands and transmitters in Germany, will transmit a minute of MFSK64 Saturday at about 1230 UTC on 6095 kHz, and Sunday at about 0130 UTC (8:30 pm EST) on 7475 kHz. Eric enjoys receiving reception reports at themightykbc (at)  gmail.com