Advice Needed 45e - 53e - signal drops massively - arc or horizon \ obstruction

manikm909

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hey guys, ive noticed that as i go extreme east, my signal drops considerably when going from 45e to 53e and nothing after it - like 15db down to 5db....is that my ARC off?

Or - is my dish being obstructed, the dish is tilted quite forward at this angle...

I guess i'll only know if i go up ladder, and see what i can get by manually altering the dish
 

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After 45E, the Satellites are getting close to your horizon so even without line of site obstructions you'll struggle.

What, in particular, are you chasing?
 

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hey guys, ive noticed that as i go extreme east, my signal drops considerably when going from 45e to 53e and nothing after it - like 15db down to 5db....is that my ARC off?

Or - is my dish being obstructed, the dish is tilted quite forward at this angle...

I guess i'll only know if i go up ladder, and see what i can get by manually altering the dish
I get the same, the further east, the more the signal drops. Some days more than others but as there is not much there for me to bother with it is not a problem.
 

manikm909

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thank you!

not really after anything in particular, just wondered if my arc was off slightly, and\or if anything AFTER 53e (and 53e) itself should be just as strong signal as 45e ....
 

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Here on the 1.25m Gibby in W.London, 51E (Berlinsat) & 52.5E (Turkmen/Monacosat) are much stronger than 45E & 46E (and also fairly strong on the fixed cheap 80cm "no name" dish with an off-set LNB ), but 53E is very marginal because of an adjacent house roof edge which is pretty much on the line-of-sight and that also blocks anything East beyond that one.

Therefore I suspect your declination or azimuth setting may not be quite right:
- if the same thing happens from 30W onwards, then I would suspect the declination setting
- but if the far Western sats are OK, or even better, then I would suspect that the azimuth setting is slightly wrong, i.e. the motor needs to be nudged very slightly East on the mast when the dish is pointing at your Southern-most sat (presumably Thor at 0.8W).

BTW: any building or tree in the line-of-sight will cause a very "sudden" drop/loss of signal rather than a gradual one.
 
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TJExcalibur

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I only get the odd transponder on 56 east using blind scan. 78 Channels. SNR 58%
 

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You should be able to get around 14-17 db on 52 and around 13 on 53 with a 120cm. It might need a small adjustment.

How's the signal on the western sats? 34.5 or 30?
 

manikm909

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34.5w - classico - reports 100% (not sure what that is in DB ) and 30w are high 80s and mid 90s....i cant go beyond 34.5w as no channle list i try lets me drive my dish that far....
 

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I only get the odd transponder on 56 east using blind scan. 78 Channels. SNR 58%
Can I ask which transponders are you receiving and what dish size? is this without the teflon inside the LNB?
 

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34.5w - classico - reports 100% (not sure what that is in DB ) and 30w are high 80s and mid 90s....i cant go beyond 34.5w as no channle list i try lets me drive my dish that far....
There's not much on Ku band beyond 34.5W that can be received by small-medium dishes, but you might be able to get China Radio (a radio channel, so not TV!) on Intelsat 14 at 45W on 11605/H/990 - a very low Symbol Rate which some receivers can't handle - and you have to switch into Radio mode to hear them. Currently I'm seeing 5 channels (which corresponds to the current Lyngsat listing) on the SX88 (which I had thought couldn't handle SRs below 1000!) at around SS 76%/SR 74% (for that that's worth!).
 

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Can I ask which transponders are you receiving and what dish size? is this without the teflon inside the LNB?
Edison SF 8008. Fibo 90. Invacom C120 LNB. Only get t he odd channel on normal scan. On blind scan filtered out up to 3 degrees. I haven't checked if it is in actual picking them up from elsewhere.
10844V-27500 Fec Auto DVB-S
10866V-22200 Fec Auto DVB-S
11195V-22500 Fec Auto DVB-S
11349H-45000 Fec Auto DVB-S2 8PSK
11736V-27500 Fec Auto DVB-S
12266V-27500 Fec 2/3 DVB-S-2 QPSK
12304V-27500 Fec 2/3 DVB-S2 QPSK
 

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FWIW, when I get relatively low SS on any sat, I find it useful to go into the settings and adjust the sat position azimuth by very small amounts (say 0.1 deg at a time) to the East and then to the West to see if the SS & SQ then improve - that way I can sometimes "peak" the position for the "best" SQ, even if the SS doesn't increase.

Having done that with the Gibby, I found that the optimum azimuth is around 0.1-0.2 deg East of the nominal on almost all sats except 45W where I need 0.4-0.5 deg - that tells me that the motor is pointing about that amount East of where it "should" be on the mast when set to my Southern-most sat (Thor, 0.8W). However, it would be almost impossible to actually make that small a correction by physically adjusting the motor position, and so it's staying where it is!
 

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hey guys, ive noticed that as i go extreme east, my signal drops considerably when going from 45e to 53e and nothing after it - like 15db down to 5db....is that my ARC off?

Or - is my dish being obstructed, the dish is tilted quite forward at this angle...

I guess i'll only know if i go up ladder, and see what i can get by manually altering the dish
If you live in an urban area, suburbia or a large city in that direction, then the drop in signal could be due to RF ground clutter swamping the LNB, also the the RF path is a bit longer the closer you get to the East/West horizon, the path loss is greater.
 

jeallen01

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....Having done that with the Gibby, I found that the optimum azimuth is around 0.1-0.2 deg East of the nominal on almost all sats except 45W where I need 0.4-0.5 deg - that tells me that the motor is pointing about that amount East of where it "should" be on the mast when set to my Southern-most sat (Thor, 0.8W). However, it would be almost impossible to actually make that small a correction by physically adjusting the motor position, and so it's staying where it is!
As "usual" I got something wrong in one part of the above - which should read " .....that tells me that the motor is pointing about that amount WEST of where it should be on the mast when set to my Southern-most sat......." :-doh
 

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If you live in an urban area, suburbia or a large city in that direction, then the drop in signal could be due to RF ground clutter swamping the LNB, also the the RF path is a bit longer the closer you get to the East/West horizon, the path loss is greater.
And additional signal loss when there is heavy cloud and rain in those directions because the path through that cloud/rain will also be longer . (We've certainly seen that in the UK with the most Easterly sats when there was very heavy rain over France & the Low Countries recently)
 
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manikm909

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amazing info - thanks everyone- hope a lot of people benefit from the advice here...
 

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My dish is high up when it’s rain heavy or high wind the pressure on the dish is more which force the dish little bit the SQ levels comes down.
To maximise the SQ level I change the longitude say from 3.1 to 2.9 OR 3.3 depends on the wind direction and it will max the SQ levels all over the arc.
 

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Captain Jack

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My dish is high up when it’s rain heavy or high wind the pressure on the dish is more which force the dish little bit the SQ levels comes down.
To maximise the SQ level I change the longitude say from 3.1 to 2.9 OR 3.3 depends on the wind direction and it will max the SQ levels all over the arc.
That's quite a contraption there.
 

Captain Jack

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I meant more the pole arrangement...
 
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