After much time doing only microwaves activities, I listened the encourage words from Luis EA5DOM, to try to receive LF and MF . Luis is active in 136kHz and 477kHz in TRX and uses Opera, WSPR and have a SpectrumLab grabber.
The most common modes are OPERA32 (32 mins period), wspr15 ( 15 mins period) in 136kHz, and OPERA-8 (8 mins period) WSPR-2 (2 mins period) in 477kHz. The OPERA and WSPR uploads to Internet the receptions as spots and is possible check online the results and distance. This is feature is very nice to compare results with another stations.
I’m really surprised for the good results and for the nice signals that can be received in this low frequencies with a small antenna. I know that this band some times not are easy for the local QRM/QRN generated by switched power supplies, motors, etc.. but with not much effort is possible get some setup to receive this bands.
I encourage that you try to receive this bands. A good point to start is the 477kHz band. It can be received easy using a base HF transceiver and antenna.
Recently I build a circular polarization feedhorn to try to do EME in 1296 MHz. The hint was that it have very easy to build and cheap. I was looking some designs based in ual mode septum designs from N2UO and RA3AQ but they not are easy to build for me. My idea has been use fireplace pipe and a dielectric depolarizer.
To build the feehorn I have used fireplace inox pipe of 150mm and a galvanized reduction from 250 to 150mm. The dielectric depolarizer is a piece of Rogers Duriod 5880. To try to minimize the number of sma connectors, I used a small piece of Suhner .141 as a probe that will connect directly to the LNA saver switch.
In the TX port I used a standard N connector. I measured the RL in the lab, but have to measure the RL in the dish for this reason the bottom plate not is soldered yet, it is glued using metalic tape, until the RL is adjusted on the dish.
Tonight, I was recording the Graves radar frequency (143.050 MHZ) to see I can detect the 2014 RC asteroid without success. But over a nice meteor has crossed Catalonia at the 04:56:50 UTC and has ben detected 🙂
The signal not is specially strong, because the target was very near from me. Using the Graves radar is more easy see meteors that are impacting from more remote locations of France or Italy
Other meteors can be observer before and after the target
The Graves radar uses a multibeam antenna system that is switched every 0.8 seconds. When a meteor is detected and prints a large trace, is easy to see the beam switching after the meteor.
As the Graves radar system uses the transmitter and receiver in different geographic locations, is easy to think that they are synchronized the the UTC.
To check if it is true Miguel EA4EOZ and me are doing stereo recordings stereo of the Graves radar in one channel and a 1PPS signal from a GPS receiver in the other channel. And efectively they are locked to the UTC 🙂
The coincidences to UTC are in the second 0,4,8,12,16,etc.. of every minute.
Some usefull info can be readed on the PE1ITR website.
According to our team “The frequency offset is ~18025 Hz on Spectravue, so it looks likely. He’s tuned to XB, so just seeing the very tip of the PM carrier.”
Phil Karn KA9Q
“I calculate a C/N0 of -2.5 dB-Hz for you, depending on mod index. Seem right? That’s weak!”
Thank you for the timestamp, qth etc, and the info about the Spectravue
I examined the file anyway and worked out that a “stereo” signal was I and Q,
16-bits each, LSB first.
I confirm the signal as you found. I averaged small and large numbers of
FFTs. This showed that the signal strength varied, between approximately
11 to 16 dB-Hz. The spacecraft is spinning at about 3 rpm, so this may be
Attached is a typical plot from my my own software. This is not the strongest
signal display; the largest I found was a signal = -45.7 dB over the
noisefloor = -53.8 dB, or SNR = 8.1 dB.
With a bin bandwidth of 0.124 Hz, this equates to a CNR of 16.4 dB-Hz.
73 de James G3RUH