DATV Beacon A71A C/N and signal strength decreased?

DL1GNM let's see what other's report, but there have been no changes on the satellite...

DL1GNM I use the NB-beacons for comparison measurements (fiddling with LNB's, lenses etc) too and learned to live with +/- 1 dB accuracy due to all kinds of fluctuations in the radio path ('QSB') , but that's good enough for me.

Hallo ...

all looks normal ... i monitored the beacon level this morning on my 85cm Offset dish...

MER ist 7.5-7.7dB (TT-S2 1600) MiniTiouner Express has the same reiceive level

Signal PEAK was 8.0dB at 11:33 local and it is ok for this high temperatures

73 de Michael dg0opk

steady MER here on my 88cm dish, no changes

Hi everybody

I've just read this thread, and with my 60cm dish I've managed to achieve MER 5.5/5.6, but today it has reached 5.9/6.0.
Hardware is MiniTiouner-Express
60cm offset dish
LNB Octagon Green

It is about 10.3 dB this morning but I have noticed it falling as low an 9.8dB in the daytime, lower if there are other strong signals.

The beacon is a bit too wide for my liking and reducing it to 1 MS or less would help with the over-crowding we are now seeing on occasion. Some stations like to transmit 1 MS and we can only accommodate two of these with the current beacon. Only one 2 Ms signal is possible and nothing wider. We all had fun with experimenting wider signals when the beacon was off. Perhaps even 500ks but H265 would be a good compromise.

Meanwhile, several of us have been experimenting with lower bandwidths and higher order modulation. 66ks is 33ks are very usable and can be done with low power.

Mike

My dish is 2.4m and the LNB is a properly modified Octagon Quad, though the MER is often better with unmodified LNBs. It is important to observe the impact of the reference phase noise and select a LO that minimises this. If using a Leo-Bodnar like I am, a change of 1 Hz can make a difference. Aim for minimum phase noise and maximum stability, not absolute accuracy as you can always correct for the latter.

For DATV use, there is no need to modify the LNB LO. However, I also use SSB where it is necessary to for the LO to be much more stable.

Mike

I think his settings will be optimum, my LNB required 25 MHz but I am not running less to have an LO of 9.5 GHz when puts all signals 250MHz higher and DATV signals into the range the Octagon SF8008 can receive them.

I think the maximum was 11.7 dB with the 30m dish at Goonhilly.

Mike

You can be happy yes. I get at best 10.6 dB. This morning, with heavy cloud and no other users, it had dropped to 10.2 dB.

When developing I noted that the phase noise is really important. For example, on the BBC transponder on BADR with an unmodified LNB I got an MER of 13 dB with a 1.2m dish. With a GPS locked LNB it was very much worse. This is a much wider bandwidth. It depends on each LNB and the phase noise of your reference. With that MER, I think you are OK.

Mike

since a few days I have problems with the beacon too.

Received it for two month without any problem, but now it looks like that:

any idea what the problem could be ?

I can receive all other signals in good quality, just the beacon makes problems.

vy 73, Kurt, DJ0ABR

dj0abr Kurt here the beacon picture looks the same. There should be an issue with the TS stream at the moment.

thank you Heiner, so the problem is not in my equipment.

I am using a 120cm offset dish.
The screenshot above shows the beacon's RFpower -65dBm.

Is this value bad/good or normal ?