Thursday, April 25, 2013
VOA Radiogram slated for April 27-28
Hello VOA Radiogram listeners,
Thank you for all the reception reports, screenshots, audio samples, etc, that you sent after the VOA Radiogram broadcasts on April 20 and 21.
Because of deadlines this week in my audience research job here at the US International Broadcasting Bureau, I have not yet been able to respond personally to your e-mails. But I will eventually.
It appears that the MFSK modes remain the most successful of all the modes we have tried. MFSK32 is a bit slow (about the speed that VOA Special English is spoken), but it rarely fails, and it can also be used to send images. It is probably time to think about receive-only software applications (app) for MFSK32, for PCs, tablets, and mobile devices.
Here is the tentative lineup of modes for April 27 and 28:
MFSK16 (preview of the program)
PSK63F (a slow but robust mode that we have not yet given a long test)
MFSK32 (VOA story with text plus image)
Thor 50x1 (for comparison with 50x2)
Thor 50x2 (because it was omitted last weekend)
MFSK128 (sent once)
MFSK128 (Flamp: sent twice)
MFSK128 (Flamp: sent 3 times) (if time)
If you don't already have it, please download Flamp from www.w1hkj.com . Flamp divides a text file into several blocks, each with a specific number of characters. If any block is received without the correct number of characters, that block is rejected. The missing block can be picked up during the repeat transmission. Flamp might be useful for those text transmissions that are received at about 90% or better copy, when occasional deep fades prevent 100% copy. In Flamp, under Configure, check both of the Auto sync boxes.
Your suggestions and ideas for future editions of VOA Radiogram are welcome.
I'll send another e-mail as the weekend approaches.
Thanks again and best regards,
Kim Andrew Elliott