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Hello
all,
probablly the software measures S/N in the 200Hz bandwith you can see and
calculates this number to a 2500HZ bandwith.K1JT cuuld tell us more.I don't see
any improvement going down from 2500Hz to 250Hz unless their are strong signals
in the 2500Hz filter wich can be rejected by the 250Hz filter.I don't see a
reason to go below 200Hz because I want to see all possible stations,this just
improves S/N number but you won't decode weaker signals than with a
broader filter .
73
Victor
Hello Rik,Andy,
normally I use a 250 Hz USB filter for wspr,I get decodes down to -32
dB although rare...
73
Victor
Andy,
maybe the "magic" lies in a
narrow filter (either IF or audio).
If I switch from a 2.5kHz (SSB) filter
to a 270 Hz filter I also get a significant increase in SNR values
reported by WSPR.
Unfortunaely it hardly affects the
decoding level (minimal SNR needed to get a positive decode), that rises by
almost the same amount.
73, Rik ON7YD -
OR7T
Has F6CNI managed some sort of magic noise reduction system, or is it a
just a case of being in a very quiet location...
These are pretty impressive S/N values
| 2010-01-27 20:14 |
G4JNT |
0.503875 |
+13 |
0 |
IO90iv |
+23 |
0.200 |
F6CNI |
JN19qb |
391 |
243 |
| 2010-01-27 20:08 |
G4JNT |
0.503875 |
+10 |
0 |
IO90iv |
+23 |
0.200 |
F6CNI |
JN19qb |
391 |
243 |
| 2010-01-27 20:02 |
PA0A |
0.503900 |
+15 |
0 |
JO33de |
+37 |
5.012 |
F6CNI |
JN19qb |
502 |
312 |
| 2010-01-27 20:00 |
G4JNT |
0.503875 |
+14 |
0 |
IO90iv |
+23 |
0.200 |
F6CNI |
JN19qb |
391 |
243 |
| 2010-01-27 19:54 |
G7NKS |
0.503920 |
-5 |
0 |
IO92ub |
+20 |
0.100 |
F6CNI |
JN19qb |
422 |
262 |
| 2010-01-27 19:54 |
G4JNT |
0.503875 |
+14 |
0 |
IO90iv |
+23 |
0.200 |
F6CNI |
JN19qb |
391 |
243 |
| 2010-01-27 19:44 |
G4JNT |
0.503875 |
+10 |
0 |
IO90iv |
+23 |
0.200 |
F6CNI |
JN19qb |
391 |
243 |
| 2010-01-27 19:40 |
PA0A |
0.503900 |
+15 |
0 |
JO33de |
+37 |
5.012 |
F6CNI |
JN19qb |
502 |
312 |
|
