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AE5ME > TECH 18.10.15 18:44l 22 Lines 1496 Bytes #999 (0) @ WW
BID : 9OYHQR0G3RWA
Read: GUEST
Subj: //WL2K Different Flavors of Olivia
Path: IW8PGT<CX2SA<N9PMO<NS2B<N0KFQ<AE5ME
Sent: 151018/1726Z 24010@AE5ME.#NEOK.OK.USA.NOAM BPQ1.4.63
From http://tulsadigitalradioclub.blogspot.com
Different flavors of Olivia
It would appear that most nets have standardized on Olivia 8-500, which has a decent tradeoff in terms of speed vs. reliability.
However, Olivia is not limited strictly to 8-500 (which stands for 8 carrier/500 Hz).
Was having problems copying a station last night on our net on 80m. I was able to switch from Olivia 8-500 to Olivia 8-250. That reduced the required s/n from -11 dB to -14 dB. Suddenly we went from 35-50% copy to 100% copy, as the other station's signal was fluctuating between -9 and -12 dB. Of course, we also took a 50% cut in data throughput when we reduced the bandwidth from 500 Hz to 250 Hz. However, 100% copy at 50% speed beats 35% copy at full speed any time!
Here is a sort summary of how the different types of Olivia compare (courtesy of the W1HKJ web site for FLDIGI):
Mode Baud WPM Duty Cycle BW (Hz) Modulation S/N ITU RSID-1 RSID-2
OLIVIA-4-250 63 20 100.00% 250 4-FSK -12 dB 250HF1B 75
OLIVIA-8-250 31 15 100.00% 250 8-FSK -14 dB 250HF1B 69
OLIVIA-4-500 125 40 100.00% 500 4-FSK -10 dB 500HF1B 74
OLIVIA-8-500 63 30 100.00% 500 8-FSK -11 dB 500HF1B 72
OLIVIA-16-500 31 20 100.00% 500 16-FSK -13 dB 500HF1B 70
OLIVIA-8-1000 125 58 100.00% 1000 8-FSK - 7 dB 1K00F1B 116
OLIVIA-16-1000 63 40 100.00% 1000 16-FSK -10 dB 1K00F1B 73
OLIVIA-32-1000 31 24 100.00% 1000 32-FSK -12 dB 1K00F1B 71
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