Help Required Motorised system fine tuning

[cwsat]

I’ve got some tinkering to do today.

I can’t get 8W now and nothing past 28.2e is coming in. No Hellas or Turksat.

 

[Mickha]

Please post some details, channels, and signal quality readings, from available satellites, 1W, 5E, 7E, 9E, 10E, 13E, 16E, 19.2E, 23.5E, 26E, 28.2E.
Try using the excellent list, by william-1:

Just Sharing This - Strongest transponders

same here,rainy weather and midday time mean weak reception for 7w and it strengthens a lot after 7pm

satellites.co.uk

 

[a33]

First, about the pole: is it completely plumb, east/west-wise? (an issue that Terryl already mentioned)

Second, with a USALS setup I would check (in fact, before all other mentioned tests):
On a diseqc 1.2 Goto-Zero or Goto-Reference command, does the motortube in fact go to exactly Zero?
And in that motor position, does the dish seem exactly in line with the line pole-motor?
And does the dish arm seem to be exactly in line with the line pole-motor-dish?

A deficiency on those points could mess up a motor setup considerably.

Greetz,
A33

 

[cwsat]

Please post some details, channels, and signal quality readings, from available satellites, 1W, 5E, 7E, 9E, 10E, 13E, 16E, 19.2E, 23.5E, 26E, 28.2E.
Try using the excellent list, by william-1:

Just Sharing This - Strongest transponders

same here,rainy weather and midday time mean weak reception for 7w and it strengthens a lot after 7pm

satellites.co.uk

Unfortunately I have no way of giving you a measurement in db’s, my receiver and meter just give strength and quality in %.

I can give you those though?

 

[cwsat]

First, about the pole: is it completely plumb, east/west-wise? (an issue that Terryl already mentioned)

Second, with a USALS setup I would check (in fact, before all other mentioned tests):
On a diseqc 1.2 Goto-Zero or Goto-Reference command, does the motortube in fact go to exactly Zero?
And in that motor position, does the dish seem exactly in line with the line pole-motor?
And does the dish arm seem to be exactly in line with the line pole-motor-dish?

A deficiency on those points could mess up a motor setup considerably.

Greetz,
A33

Pole is definitely plumb and yes, the motor is at zero on reference.

All brackets level, dish is central to motor.

I’m going to check the pole when the dish is round at 42e.

 

[Mickha]

% signal quality readings are fine. It gives us an idea of h ow the dish is tracking the satellite arc.
If you read william-1's thread you'll see his readings are in % levels.

 

[deeptho]

a33,
I mean: use both the modified values. This will also lead to the dish being slightly higher up in the center.

About the fine tuning: it depends how it is done and of course you can give preference to a weaker sat if it
is of high interest

 

[cwsat]

Issue with the eastern sats I have pretty much resolved, it was due to the height of the dish on the pole mainly, although I have adjusted the declination angle. I have a 6ft wall not far from the dish and it was interfering with the sats in past 28.2e.

I have set the motor latitude back to 52.5, what it should be.

I am getting right round to 52e now and Turksat is a lot stronger. 28e is stronger than my minidish now but I have had stronger quality readings from my 85cm than what it’s performing currently.

8W is back.

I will post some strongest transponder results later.

I lowered the dish initially because the pole was rocking in the wind. It’s still a concern. It needs concreting really.

 

[Manikm909]

always tweak on 1w, not at the extremes. sounds like you're getting there...nice one.

 

[deeptho]

always tweak on 1w, not at the extremes. sounds like you're getting there...nice one.

Indeed. So check what is wrong at the extremes, but make the adjustments only after rotating the dish to 1.0W. Quality could also
be related to LNB skew, but it is best to optimize skew on weaker sats.

 

[a33]

always tweak on 1w, not at the extremes.

As far as I'm concerned: you can tweak dish declination at the extremes.
But indeed, after that, adapt the motor elevation again at the center of the arc (at due south/ 1W for you).

This is a repeated steps procedure of tweaking the dish declination angle (at the extreme), and then take compensatory action on the motor elevation (at due south).

Greetz,
A33

 

[deeptho]

As far as I'm concerned: you can tweak dish declination at the extremes.
But indeed, after that, adapt the motor elevation again at the center of the arc (at due south/ 1W for you).

This is a repeated steps procedure of tweaking the dish declination angle (at the extreme), and then take compensatory action on the motor elevation (at due south).

Greetz,
A33

You can if you want (I have done it as well), but it is tricky and can be confusing and you can easily end up in a situation where
you need to restart from scratch.

You need to measure anyway at bot extremes to find out what is the problem (if there is one). The worst problem is a non-vertical (in east-west direction) pole. There is not much that can be done about that, except for introducing some slight errors in declination/elevation to minimize the worst error, or -if your dish is on a ground stand secured by tiles, by throwing some extra dirt underneath one of the sides. This is remarkably
stable over time.

These days, I tend to rely on measurements for all but the very final tweaks.
I found that it makes things easier. A light-weight dish also helps a lot. E.g., the laminas 120 cm was quite easy to adjust, compared to another noname (steel) dish I tried before and which also gave worse results.

 

[a33]

These days, I tend to rely on measurements for all but the very final tweaks.

I totally agree to that approach.

Setting the best possible elevation/declination angles (using the modified angles),
and setting the apex (highest point of the arc) as best as you can (using USALS, or a rotation/dish-rim-displacement calculation for a non-USALS setup, when your 'reference' satellite is not exactly due south),
are the best starting points to make tweaking easier, I would say.

Greetz,
A33

 

[cwsat]

What would you chaps recommend as a good channel / frequency to check my skew and elevation at 1w?

I usually use Sky News but on my meter it tops out at 85% quality on my meter.

Could do with something weaker?

 

[Channel Hopper]

One of the Nordic beams , 12.322H for example.

Thor 7 at 0.6°W - LyngSat Maps

 

[cwsat]

Is the K1 beam worth playing with?

Seems to be significantly weaker.

 

[deeptho]

One of the Nordic beams , 12.322H for example.

Thor 7 at 0.6°W - LyngSat Maps

Another solution is to use a mux with a frequency on which both H and V is transmitted.
If the skew is off both polarisations will interfere.
E.g. 10747H and 10747V. Just a theory. I have not tested it myself but ut cannot hurt to try.

For a mux which has no such interference, you basically count on background noise but if the mux is too
strong the sensitivity will be low. Some people also insert a wet cloth before the lnb to simulate rain fade.

In general it is always best to try multiple muxes. There could always be some interference from neighboring
satellites which might complicate readings.

 

[cwsat]

What I am noticing, and it's prevelant on 28.2e is the dish needs more skew it seems.

If I skew the LNB when at 28.2 the quality 11264H goes up from 67% to 78%.

What is weird is 11126V is at 80% with the skew at zero.

Unfortunately skewing 28.2e has a negative impact on the other sats like 16e,13e and 1w.

 

[Channel Hopper]

Is the K1 beam worth playing with?

Seems to be significantly weaker.

Can you receive the one I mentioned ?

 

[cwsat]

Can you receive the one I mentioned ?

Yes 92% Strength 70% Quality.