Digital Satellite Meter ... Does anyone know how to use the SF-500A pics below

Y

YNAYNA

Member
My Satellite Setup
TM-600
My Location
UK
Hi all ,

I bought an SF-500A Digital Satellite Finder to help align my dish a few years ago and just couldn't get the thing to work properly. Mainly because the pre-installed satellites within the finder are not for this country ...

I can enter my own details for Astra 28.2e but I cant get hold of the information on the net anywhere. Either that or I'm not recognising the data when it is presented ...

This Sat finder has two screens of information to input to set up a satellite ... Pics Below


Could anyone help me out and let me know the figures for :
LO Freq
22k (On or Off)
Down Frequency
Symbol Rate
Polarity

I presume you pick on one channel on Astra 28.2 and input the figures for that and hopefully all the rest will be fine ???

Please help ...

Thanks in advance

YNA

P.S The figures you see inserted are my efforts from the net for BBC London and not built into the sat finder ...
 

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This video may help you with some of the meter settings..


I noticed that the meter in the video has Astra 28E listed at #11 on his screen. You'll need to set LO to Universal and 22K to auto.
 
You can look up the reception settings of satellites at Lyngsat: https://www.lyngsat.com/
There you go to Astra 28E and select a few relevant transponders.
They come in a format like: 11.450MHz SR27500 FEC2/3 8PSK
What does that mean?

11.450MHz is the downlink frequency
The LNB will convert this to the L-Band, which your receiver will tune to: 950MHz-2150MHz.
Because Ku-Band satellites use 2GHz bandwidth, this is divided in the Low and High band. The 22kHz signal (on/off) will tell the LNB which band (Low/High, L/H) should be converted. For this the LNB either uses a Local Oscillator Frequency (LOF) of 9.750MHz or 10.600MHz.
In order to render the received frequency correctly, the meter needs to know the LOF, so it can add it to the frequency, i.e. transponder at 1.100 MHz in Low-Band. Add 9.750MHz and the satellite downlink frequency is 9.750+1.100 = 10.850 MHz.
The sat-meter does not know what the LOF of the LNB is.
SR is the Symbol Rate, i.e. how many bits/second are sent
FEC is the amount of checksum bits that allow to correct wrong bits
QPSK = DVB-S modulation
8PSK = DVB-S2 modulation

You would typically want to measure a transponder in each band (L-V, L-H, H-V, H-H). Note that the second letter refers to Vertical/Horizontal, which is controlled by the LNB voltage (13V or 18V).

Hope this gives you a rough idea on the principles.

Cheers,
Vitor
 
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