I googled this article about Snow Microwave Reflection at Mobile Phone Frequency Bands. What means "reflection loss" in this context ? More or less reflection ?
WB BEACOn MER
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Hi all,
Just installed a new dish-antenna, prime focus 180cm.
The beacon give me a MER of 11.4 on this moment.
Now is my question is this a good value for my dish-antenna?
I have no reference so no way to check that number.
But what is MER, how is that calculated?
Means 3dB MER more also double the power, same as by a HF-amplifier
73,
Bert
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Looks like it is almost the same as C/N:
https://en.wikipedia.org/wiki/Modulation_error_ratio
https://en.wikipedia.org/wiki/Carrier-to-noise_ratio
And D5 value mean Link marginLink margin = CN - CNmin
CN - actual C/N or??? MER
CNmin - minimum C/N to decode DVB-S signal.For DVBS-2, 7.2 Msym, 8PSK, 3/4 FEC C/Nmin is 7.9 dB.
For DVBS-2, 1.5 Msym, QPSK, 4/5 FEC C/Nmin is 4.6 dB.
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Hi Bert,
I am also using a 1.8m dish.
MER here is maximum 11.9dB.
If there is more traffic on the transponder the MER goes down.
Thus your MER of 11.4 sounds right.
Kind regards
Matthias
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Danke Matthias,
This is my modified LNB.
For the whole construction LNB/sat-dish see my homepage
https://www.pa3aod.nl/HamRadio/Satellite%20Dish/index.html
73,
Bert
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Hi Bert,
I looked at the pictures on your website. It looks all very good!
Here is a picture of my dish:
[Blocked Image: https://www.dd1us.de/images/dd1us%20qo-100%20dish.jpg]
Kind regards
Matthias
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Here in JN61FQ with 100 cm dish, octagon twin LNB, MER = 11.1 dB, +2dB compared to before.
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Seems to be that I've some space for improvements...
A71A bcn: MER 10.7dB (8.9dB before change of the beacon)
1.2m offset dish, see here DL1GNM going to be QRV soon
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Typically around MER 12 with nobody else on. It's 11.6 at the moment as the transponder is fairly busy, but no big 1 MHz carriers. When they come on it drops quickly well below 11.
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Tried these unmodified LNBs without any improvement:
Megasat Diavolo Twin
Octagon Green HQ OTLG
Opticum Twin LNB LTP-04H
