Just Sharing This My sat setup (Part 2)

[Fisty McB]

Well having moved on a bit from earlier this year I've got myself a motor to move on from just a multi-lnb setup (although I do plan in coming back to that) which I talked about in this thread. I haven't touched it yet since I first set it up other than to add a new LNB (mentioned below) slightly adjust my longtitude setting on my receiver which seems to compensate a small arc-tracking problem. Not really sure if I should go back to it yet as I'm worried a little bit that I'll screw something up!

Anyway, dish is a 1m CDtronix, motor is an Alsat Dark Motor Superior from World of Satellite, LNB is a single output Inverto Black Ultra with single output - I was planning in originally getting a double or quad output but I decided to leave it for now to see where the best focal point is as on this dish it appears to be quite far forward from the front of the arm though I haven't had a chance to properly look at it yet. Cable at the moment is come RG6 with CCA core and aluminium braid & foil. When a more permanent installation is ready to go in the WF100 is sitting there ready to use. 1 metre tall patio mount, attached to heavy flag paving stone with coach bolt which can be adjusted to be plumb with additional nuts & washers. No sandbags at the moment, but a couple of spare sand & gravel bags will do fine in the meantime.

Oh, and you can see where the tyre is in one of the photos. It's days for propping up satellite dishes might not be numbered yet though. ;)

 

[RimaNTSS]

to see where the best focal point is as on this dish it appears to be quite far forward from the front of the arm though I haven't had a chance to properly look at it yet.

What is your plan to find this true focal point? To find it mysterious "Le point G" :mad: is better to use some program to calculate position of LNB.

 

[Fisty McB]

What is your plan to find this true focal point? To find it mysterious "Le point G" :mad: is better to use some program to calculate position of LNB.

The method I use not only to try and find the "sweet spot" of LNB placement & skew, but also to fine-tune elevation & azimuth, is to weaken the incoming signal by using a damp tea-towel to simulate rain-fade.

I take a tea-towel, soak it under a cold water tap, ring it out (not too hard) and then standing behind the dish drape about half the tea towel over the top - then look to the signal meter on your screen (in my case I use a portable DVD player with an AV input as I do my work at ground level) from the receiver to notice if the signal quality has dropped. If the picture has completely disappeared and signals are nil, then I need to pull the tea-towel back a bit until a picture returns, preferably without break up. If there is no noticeable change in signal quality, then I slowly slide the tea-towel down the face of the dish until there is a change. The idea, where possible, is to cause a reduction in signal quality without the signal completely disappearing.

Once the tea-towel is "fixed" at a point where you now want to make adjustments you can use a couple of clothes pegs to clip it to the top rim of the dish to stop it slipping down the dish face. You can then fine-tune the azimuth, elevation, LNB position & skew to get your signal quality back up if it's possible - once you've got a "maximum" in this position, tighten the nuts & bolts up somewhat (not fully tightening them as adjustments might still be needed), you drape the tea-towel a little more forward to weaken the signal quality again and this time, gently pull the dish from behind at it's top, bottom and its sides and watch the signal meter on the screen - if the signal drops equally on each plane (top-bottom & left-right) with an equal force pull, then the elevation & azimuth is pretty much spot on and you can tighten those nuts - carefully & equally of course to ensure this sweet spot isn't lost. Otherwise the dish will need a further fine-tune in it's position.

Once it's elevation & azimuth can't be improved, then go back to the lnb and make some very slight adjustments to its position and skew - if there is no improvement then the LNB might be already at it's best focal position & skew though draping the tea-towel a little bit further over the dish face again might help. Once this is done everything should be in its best possible position relative to everything else. And remember to take the tea-towel off when you're finished!

I find this works well on satellites with strong signals e.g. 13, 19, 23.5 and 28 east as although they can be easy enough to lock on, using my method above means you can maximise what you can get so that signals remain in all but the very worst downpours. For weaker satellites it can be a bit more of a challenge to find a point where you can weaken the signal quality using the tea-towel without causing it to go below the tuner threshold and the signal disappearing but it can be done.

Probably not as accurate as a professional meter than can measure the BER, but as a method and technique that costs next to nothing I find it works very well.

 

[Fisty McB]

Ok, well a few things have taken place over the summer & early part of autumn to develop I suppose what could now be called a dish farm.

After getting a Vu+ Duo2 as a present, I decided to bite the bullet and look at getting two dishes in, one motorised and another fixed. Conduit was bought & dug in to reach the two expected locations, the motorised dish was moved slightly closer to the house to move it away from the fence (I suspect it was blocking far eastern satellites). A self-bodged standing pole bracket was made, first by making a "foot" frame using some old wood my parents had into the shape of a V with thicker wood attached to the bottom, where an old Sky Zone 2 dish wall bracket is bolted on. The contraption is then buried with only the bracket visible above ground, the depth of soil covering the frame is around 12cm. Then attached is a 34mm thick 1.5 metre steel pole, which has been spray painted black and has outer rubber bungs attached to both ends, this sits within the bracket and is manually driven as far into the soil as practical - not a big depth but it helps. The bolts on the bracket are then attached and now a free-standing pole is in place.

The only problem was that when I finally went in to install the 80cm dish for multi-lnb reception I soon found out that the oil tank and protector in front of it was too near for the dish to see over it and I had done my original maths wrong! A potential disaster, but in the meantime I used an old balcony bracket to attach the dish to a nearby steel pole that supports a washing line. I tried to keep the dish as reasonably low as possible - I could have attached the dish directly to the pole instead of using the bracket, but this could mean bolts sticking out at the back of the dish catching someones clothes walking along the path, so the balcony bracket with its bolts 'inverted' changes this.

After that it was decided to gravel the back garden. In the process I found that 28 east on the black pole was just visible to the left of the oil tank guard so my Zone 2 dish was put into affect for that.

More later, I have an appointment to get to but I've attached some photos...

 

[Fisty McB]

...continuing.

Of the four LNBs on the 80cm dish, only three are currently "active" - 13 east (centre), 19 east & 23.5 east. Prior to the Zone 2 dish being deployed, it was centred on 19 east with 13, 23.5 and 28 east added - while 19, 23.5 and 28 were OK, 13 east was a little weak. It appears the Hot Bird footprints fade out a bit more as you move north-westwards across Ireland than the footprint maps suggest and while fine for the stronger DVB-S transponders, several weaker DVB-S2 transponders were borderline & easily getting lost in just light rain. So with an Inverto Black Ultra Quad purchased and fixed on to the motorised dish, the single output IBU was reassigned to the 80cm dish for centre focus on 13 east. It's now rock solid for all transponders at 13 east, 19 east is almost as good as it was at its centre focus. The 23.5 east LNB needs to be slightly pulled inwards to maximise signal quality levels, hence the use of some twine attached to the top of the pole! The other LNB, a Inverto green Eco LNB has been intended for use at 9 east, but the spacing is just too tight aside the IBU for 13 east to get the best spot for it. A similar trick to that used for 23.5east only gave some limited results while also upsetting reception at 23.5 east itself. I'll have to go back on the drawing board for that, but I think it could be achievable - otherwise 5 east is an alternative option.

With the old Homebase bags of fine gravel and sharp sand used to provide a firm foundation for the new motorised dish position, the extra weight has been temporarily provided by two large stones I dug up out of the ground in the front garden! It's done OK so far in holding up to some winds gusting up to 40mph (65km/h) but looking at the set up oscillating makes me think it might not be enough for some real stormy winds, so I'm planning on going up to a relations farm this weekend to get some large blue stones (very dense). The end result should be sufficient weight holding down the flag stone (somewhere between 50-100kg) but look more pleasing than just a few sandbags especially among the rest of the gravel.

The Zone 2 dish is bringing in the UK spot beams at 28 east rock solid now and given a big improvement to some weaker Eutelsat 28A transponders that were starting to break up in anything more than light rain when it was originally sourced as an offset on the 80dm dish. Depending on (hopefully!) Astra 2G getting into orbit and getting into service, if previously weaker signal levels show another notable improvement I might replace the Zone 2 dish with a 45-50cm standard and either reuse the Zone 2 for 53 east or give it to my parents (whose original Sky Digital dish is now around 14.5 years old and starting to show signs of corrosion that might suggest it hasn't long left) or my brother in Belfast who has taken an interest in getting FTA satellite.

The motorised dish is able to easily enough get from 46 east to 30 west now. I have been able to get 53 east in the past here using the Zone 2 dish, but the motorised dish can't see it - I'm not sure wherever it's because it still can't clear sight of the fence or wherever the trees in the distance provide an effective block when in summer bloom. With the leaves starting to fall off, it might now start to come back in time, otherwise I might throw one more dish up above the current Zone 2 dish on the black pole to point at 53 east. If that isn't necessary, then I'll trim the black pole down. Going westwards, in the old position I was able to get weak signals from 45 west but not at the moment even though I've calculated it should be clear. Nevertheless there's only a couple of channels there and beyond 30 west there doesn't appear to be much exciting activity there anyway at least for Ku Band. There's three feeds from the LNB, one goes via the motor into the Vu, the second one also goes into the living room for a future second receiver for specialist feed hunting, while a third also goes into a bedroom for a potential future PC DVB-S2 receiver. All cables except the very last one are WF100 - the reason for the last one was that I ran out of coax by the point of that last run so I decided to reroute the RG6 that was previously there for the bedroom run.

Diseqc switch is a 1.1 10/1 Opticum which works fine, keeping it out for potential LNB expansion otherwise I would have used an old Technomate 1.0 4/1 switch which I'd guess could still be cascaded in if needed later. The coloured zip ties on the coax cables are to make identifying which cable is what from each LNB easier at the switch.

I think that's all for now, I guess future plans are to spray-paint the dishes to blend in with the surroundings better and see how many LNBs I can get away with adding west of Hot Bird on the 80cm dish.