December 20th, 2016
There is some nice troposheric propagation this afternoon. It looks promising for the NAC, IAC and UKAC this evening on 23 cm. When looking for DB0XY I saw this situation:
During the morning I was able to monitor GB3FM in IO91OF on 1297.050 MHz and G8MBU in IO90IR on 1296.800 MHz. Now in the afternoon F5ZCS in IN87PT on 1296.959 MHz came out of the noise with a strong signal of 549 with fast QSB. It is my 53rd beacon on 23 cm. The weather here in Mainz doesn´t look like tropo: 8/8 cloudy and wind at 40 km/h.
Listen to F5ZCS:
A long time monitoring of the beacon F1ZMT in JN07CX via Aircraft Scatter on 1296.872 MHz shows asymmetrical reflections on most of the crossing planes.
As the distance to the beacon is 624 km and it´s ERP of just 10 W (a panel antenna to the south combined with an omnidirectional big wheel) is rather QRP, only weak reflections can be detected from time to time. This ensures, that received signals were reflected on single airplanes. In this example can be seen, that the reception starts shortly before the plane crosses the path between DJ5AR in Mainz and F1ZMT in LeMans. Unexpectetly the signal can be seen for quite a while after crossing. There is a continuous variation of the doppler shift and no spread of the signal, as is usual for a moving solid reflector.
The monitoring of distant beacons can be a boring job, even when using the waterfall diagram of a SDR. I prefer SpecJT of the WSJT package in JT65c mode. It is much more sensitive and even at slow speed faint refections can be seen clearly.
The example shows F1ZMT in JN07CX, 624 km from Mainz. The beacon operates 10 W into an omnidirectional antenna on 1296.872 MHz. The reflections in the screenshot were caused by 3 airplanes crossing the path one after the other.
As EA2TZ/B is one of the widely observed beacons, it had been missed during the last months. Now it is back on air again after adding some improvements, as Josemi, EA2TZ, informed today.
Power: 10 W
Locator: IN93BF88cp ( N 43º14,69´ W001º50,95´ )
Altitude (m): 653 m asl.
Antenna: 2 x Big Wheel (omnidirectional)
If the beacon can be heard, please spot it and don´t forget to add the “/B” to the callsign.
There are good tropo conditions to the east from here for quite a while. I worked OK1MAC on November, 26th with an outstanding signal. OK0EA, SR6LHZ can be monitored constantly. I missed OK0EL on 1296.940, but solved the miracle today. The frequency shifted to .942 and the signal has been covered by DB0AJA. It´s nice to listen, how OK0EL in 526 km distance is battling against nearby DB0AJA,131 km away. As can be seen, DB0AJAs signal is accompanied by several dopplershifted reflections on airplanes.
It is interesting to see, that F5LENs refractive index as well as Hepburns tropo index don´t really illustrate the real conditions today. The conclusions is: Always perform a beacon check before switching off! The result may be surprising.
Last night, when I was going to switch off all the stuff in my shack, I saw an email from Malte, DE7LMS. I opened it and found a link to a video he recorded of my recent presentation in Weinheim.
My presentation “Let´s Bounce” will be given on two more dates:
October 25th, 2014 on the 4th Hessian GHz Meeting in Fernwald
Short version of the lecture with focus on aircraft scatter and ISS bounce.
We meet at 15:00 MEST on the car park at the town hall. There will be a flee market for GHz stuff and the opportunity to test own equipment or to have QSOs with other participants.
Oppenröder Strasse 1, 35463 Fernwald-Steinbach
November 7th, 2014, 20:00 MET on the monthly meeting of DARC OV Miltenberg, B24
Full Version with overview of propagation modes, aircraft scatter, ISS bounce and visual moonbounce.
Deutscher Amateur Radio Club e.V.
Ortsverband Miltenberg, B24
Gasthaus “Goldenes Faß”
Kirchstraße 13, 63920 Großheubach
If you like to attend or need further information, just send an email to dj5ar (at) darc.de
Jürgen, DK2AN phoned me tonight, to tell me, the new beacon DB0XY will be transmitting on 1296.910 MHz. It is located on the Bocksberg in the Harz mountains in JO51EU, about 750 m asl. The power is 10 W into a 4 times double quad, omnidirectional. The keying is in A1: callsign, locator, carrier, dashes, carrier….
In a first quick try it could be received here with 519 to 539 via tropo. When Planes crossed the path, the signal increased up to 559.
Another beacon will be installed on 13 cm soon. The intention is to provide beacons for monitoring via aircraft scatter.
Please spot any reception in the DX cluster.