R2AJA's blog

Tonight, I've looked for WSPR spots on LF, MF, 160M.
Strange spots I've seen.
Callsigns, powers, distances is fantastic!
Here It is:
Timestamp Call MHz SNR D Grid Pwr Reporter RGrid km az #
2018-12-30 05:18 O12TUC 0.137486 -29 0 KJ57 0.05 DL0AO/2 JN59vk 4997 342 1
2018-12-30 05:18 BJ3EQF 0.475617 -30 0 MH76 0.02 N2BJW FN34im 15444 325 1
2018-12-30 05:54 027FYN 1.838154 -29 0 KC19 100 OZ7IT JO65df 12905 353 1

From WSPR 3.0 User’s Guide we know that computer clock must be correct to within about ±1 second.
I've tried to test it and find practicullar limits of error.
First PC is receiver, and have internet time sinchronisation.
Second PC is tranceiver and I setup clock as I want.

We can compare DT parameter on first PC, and get or get not spots from other WSPR world stations.
Band is 40M. Power is 0.5 W.

Accuracy clock manually setup is near one second.

1) We can't receive second and higher harmonics of WSPR signal because
a) Subband's WSPR is not multiply on different bands.
Example: CW Signal 7030 KHz, second harmonic is 14060 KHz may be received by skimmers or operators.
WSPR signal 7040.100, second harmonic is 14.080.200 and not in 14.097.000...14.097.200 subband.
b) Four frequences of WSPR signal will have wider step in higher harmonics and could not be decoded.
See WIDER-2F-wspr.PNG

I launched WSPR 2.12 on a Pentium 3 1200 MHz PC.
But it can't work normally.
The error in screenshot
What's it?

Is there modulation such as WSPR, but without using realtime?
I want make automatic beacon, without precision clock.

I've get error with small Fiq (Hz) frequence.
I used ZetaSDR and I/Q mode.
ZetsSDR's L.O. Freq = 10.139.910, Dial Freq = 10.138.700
Fiq (Hz) = Dial freq - L.O. freq = -1210 Hz.
WSPR 2.12 have runtime error with this Fiq (Hz), see images in attach!
I try other Fiq (Hz) numbers:
-7000 Hz Ok
-6000 Hz Ok
-5000 Hz Ok
-4000 Hz Ok
-3000 Hz Bad, error!
-2000 Hz Bad, error!
-1000 Hz Bad, error!
I try other Fiq (Hz) positive numbers:
3000 Ok
2000 Ok
1000 Ok
0 Hz Bad, error!
What can I do?

We know that Frequence difference is 1.46 Hz.
Can I use step 1 Hz or 2 Hz?
Could It work?

I test WSPR-X software.
It do not decode! I see message box:
"At line 34 of file wsprd.f90 file: "Files\wsprx\save\171230_1154.c2"
Traceback: not avaiable, compile with -ftrace=frame or -ftrace=full Fortran runtime error: ////////// "
What is It?

What happens to the decoding signal, with QSB?
The essence of the experiment:
Turn on the receiver in the given time and look at the WSPR decoding.
1) Receive for 1:30, 1:00 (full signal around 1:50). Decoded! :woohoo:
2) Receive for 0:30. Does not decode.
3) Receive within 1 minute, shifted relative to the start signal for 30 seconds, i.e. from 0:30 to 1:30. Decoded!
In the picture a visible signal (1:50; abbreviated: 1:30, 1:00, 0:30; 1:00 with an offset).
The result:

I test WSPR beacon on 10M band. Beacon on Si5351+Arduino+BS170 AMP radiate only 10 mW. My antenna is wire 10 m long, 4 m upper the ground. Beacon is working two weeks continiously. Some spots:
2017-12-12 17:28 R2AJA 28.126060 -27 -1 KO85xt 0.01 PG0DX/1 JO33ce 2052 275
2017-12-12 17:04 R2AJA 28.126049 -26 0 KO85xt 0.01 OZ7IT JO65df 1608 278
2017-12-08 12:38 R2AJA 28.126028 -11 -3 KO85xt 0.01 OZ1FJB JO55si 1651 279