Fringe reception - weak signals

Haroldinio

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How can one fine tune a channel?

If the frequency is 12500 can you manually adjust to 12450 to get a better and more consistent picture?

Harry
 

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Tuning that far off won't work.

Each Transponder occupies somewhere around 20MHz of Bandwidth, so to "off tune" by 50 MHz is going to put you on an adjacent Transponder to the one you want.

But you can try altering your nominal centre frequency by no more than 5 or 6 MHz: In your example, as low as 12494 and as high as 12506, perhaps.
 

Haroldinio

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Many thanks!

May I also ask...

The additional stats for the channel are :

Symbol Rate: 3333 Ksyb/s

FEC 3/4

In terms of fine tuning, should anything be done with the above figures?

The slight frqeuency adjustments have so far been unsuccesful and have not solved the problem of a pixelating picture.
 

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The Symbol Rate and FEC shouldn't be altered.

Some Receivers don't perform well too well with relatively low Symbol Rates such as that, though.

What size Dish are you using and exactly which Channel are you having difficulty with?

Odds are, you need a bigger Dish ................
 

Haroldinio

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Tivù said:
The Symbol Rate and FEC shouldn't be altered.

Some Receivers don't perform well too well with relatively low Symbol Rates such as that, though.

What size Dish are you using and exactly which Channel are you having difficulty with?

Odds are, you need a bigger Dish ................


The parameters are :-


Satellite: Hellas Sat 2 (39°E)

Reception Freq: 11146MHz

Polarization: Vertical

Symbol Rate: 3333 Ksyb/s

FEC 3/4


We have a one metre dish. What you suggested re the receiver is accurate in my case.

My set top box is a Triax DVD 262 S but when we tried a borrowed Technomate the channel could be received.

I am wondering whether a new dish i.e. 1.1m metre dish would be preferable or just to go for a new receiver? or both??

WHats your advice?
 

Topper

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I think you already know the answer here, the tuner on the Triax DVD 262 S is presumably incapable of resolving such a low SR.
All tuners are different and if you can receive what you want with a Technomate this suggests that the dish is big enough provided you use a TM stb. If you use some other stb then yes you may need to increase the dish size to overcome the low receivable signal
 

rolfw

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A friend of mine had a problem with that transponder with his Triax 110s, but realigning the dish brought it back in. Not guaranteed in this case, as some receivers (as mentioned above) have problems with these low symbol rates.
 

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Yes, I've had three alignments bring back Riksat on selected receivers. More likely to be a low SR receiver problem here though as mentioned but well worth a look.
 

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General issues in case of weak signals (others than going to bigger sized dish and adjusting lnb skew).

1. Use good quality LNB.
2. Use short cable, as much as possible, also, use best quality cable (going to double braided/full copper core won't help much, not worth investing)
3. Use good quality connectors (preferably, crimping ones, avoid screw-on types)
4. Use as few connectors/joints as possible, remove any DISEQC, switches, splitters, etc.
5. Use receiver with sensitive input (don't believe to marketing ads, better to ask on forums).

All above can easilly gain 10-15% in picture Q.
 
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