poor Freesat in Alicante, Costa Blanca 2.4m Fortec Star dish

[guest poster]

I did say the Invacom's got the reputation there.. but we've beaten c120s enough times to know it's not that cut and dry... although not on 2d there but 7w h's here (similar problems.... but not the same I agree). but I'd never say never ( well, apart from just then). there's just too many making lnbfs.... and too many reports of beating that feed horn on their own dish..

What do you think of the issue of the focal point that most LNBfs get on that dish without serious modifying and the F/D ratio you'll get using an LNBf.... that's not any easy mod' either to get right with those arms (unless you have the tx arm).

The internals/spec on an Invacom quad LNBf v C120 are identical.

Feed horn & feed support arms shadow are pretty low compared to the surface area of a 1.8m...

as a percentage of surface area, what do you think it is including the feed horn & arms......

 

[guest poster]

Right guys, thanks again for all this info, that i need to use the technical dictionary to understand ( ) jejejeje.....
Anyway so if i go for the "Fortec Argh" and i get it correctly build up, getting an invacom c120, with the feedhorn that it comes (as both of you agreed that is the right one for a Prime Focus Dish) this should be then a matter of adjustement and presition.....
However, Snap said that the OffSet Dishes has betta results for the reception on BBC/ITV ( Freesat) channels in the Alicante Area.....could anybody tell me which is the most suitable dish (prime focus, off set ) type and size for the area i am (remember i am Near to benidorm in Alicante (latitude 38.5903° longitude -0.1311°)......
I understand this is not a easy goal to achieve but i am still stuborn and short of money enough to believe that this dish is complete rubish .....(mostly short of money jejejejeje).

Thanks and looking forward for your reply
Andy.

The differences between offset dishes and prime focus dishes are argued quite a bit.

One issue is the lnb & support arms cast a 'shadow' on the prime focus dish so nicking a bit of your signal where the offset doesn't. But the area is usually very, very small as a percentage on larger dishes.

Also, the offset dish sits more upright than the prime focus for 28e in Spain. With the strong winds coming off the med in winter the offset gets it more 'head on' and especially with the webbed back of the ASC's which trap wind (... and we all know the problems with trapped wind).
The ASC's are made from a composite of resin/ fibre glass and can 'flex'. They spring back ...but will lose some signal on dish distortion and temp' forcing 'off sat'.

A prime focus is far more shallow horizontally getting the wind more from the side and it's edge can instead cut the wind blowing through it & can be sheltered by a fairly low wall round a patio.

 

[neoandy]

The differences between offset dishes and prime focus dishes are argued quite a bit.

One issue is the lnb & support arms cast a 'shadow' on the prime focus dish so nicking a bit of your signal where the offset doesn't. But the area is usually very, very small as a percentage on larger dishes.

Also, the offset dish sits more upright than the prime focus for 28e in Spain. With the strong winds coming off the med in winter the offset gets it more 'head on' and especially with the webbed back of the ASC's which trap wind (... and we all know the problems with trapped wind).
The ASC's are made from a composite of resin/ fibre glass and can 'flex'. They spring back ...but will lose some signal on dish distortion and temp' forcing 'off sat'.

A prime focus is far more shallow horizontally getting the wind more from the side and it's edge can instead cut the wind blowing through it & can be sheltered by a fairly low wall round a patio.

Many thanks Pedro, so the answer as you said is a matter of preferences, with both dish systems you can get the "bloody" 28.2E, you are making your point to say that a determinant agent as wind can afect the reception, as in any system with any dish, thanks for that tip.

Will the dish lose signal strenth or quality by being a segments dish rather than being one piece?
Can we do not solve this problem by usng any fixing material as construction or pipes ones ?
And finally paceing the dish on the ground, with no obstacle pointing south, and being covered by a wall behind and n the side, will this not stop the wind by swingin the dish and moving it form its original point?

Many thanks .

PS: So in a 2.4 meter dish prime focus, it won´t matter the lost of signal, as is a big dish.

Cheers

Andy.

 

[guest poster]

you can have walls all round sheltering the dish.. so long as the angle up to the satellite is clear.. not as difficult with a prime focus..

you do lose on the joins.... another issue.. although there is one big join on the 2.4 CM...it's not a lot but it all adds up. you could put some ali tape or something over the join... but it might look awful..

btw..

both the 1.8 & 2.4 asc's are bigger in surface area than FS's... they are oval and their width is 1.8 / 2.4 but taller ... where as a prime focus is circular but the view by the lnb is considered the same (by some) in offset (it sees a circle of 1.8 or 2.4). I disagree to that as well as both the 1.8 & 2.4 (& 1.2 etc...) are all larger in catchment area that is reflected into the lnb.

We measure diagonally always to calc surface area .. ..You need to compare apples with apples.... surface area v surface area..

Anyway, it's usually a price thing.. £170 v £2600-£3000+ etc... but if one was to choose a Fortec Star ... it has to be put together very accurately, very carefully so not to buckle it ... use the right lnb /feed horn ...

......and when it's 100% .... seriously strengthen it with some diy engineering.

 

[dxsat]

However, Snap said that the OffSet Dishes has betta results for the reception on BBC/ITV ( Freesat) channels in the Alicante Area.....could anybody tell me which is the most suitable dish (prime focus, off set ) type and size for the area i am (remember i am Near to benidorm in Alicante (latitude 38.5903° longitude -0.1311°)......
I understand this is not a easy goal to achieve but i am still stuborn and short of money enough to believe that this dish is complete rubish .....(mostly short of money jejejejeje).

Thanks and looking forward for your reply
Andy.

Andy-
If money is tight you had better go for the Famaval (Portugese) and fit it with an Invacom quad and Invacom ADF-120 feedhorn (both available directly from Invacom)
Some facts which are indisputable:-
•Prime focus dishes HAVE to be fitted with a C120 LNB and adjustable prime focus feedhorn. They should NEVER be fitted with a LNBF or one- piece LNB.
•Installers in your area typically fit prime focus dishes with a LNBF as they are cheap (for the installer- typically less than 10 euros for a Sharp or similar)
•Offset dishes have higher gain than prime focus of the same size. The reasons are complicated but they relate to laws of nature not opinion.
•All dishes larger than 120 cm work better with a C120 LNB and feedhorn matched to the dish, particularly for BBC & ITV (Astra 2D). Dishes larger than 120cm will work with a LNBF fitted, but never to their full potential.

The idea that ASC signal dishes 'flex in the wind' is one of the more ridiculous things I have read for some time. They are highly stable and have the strongest support structure of any dish made for direct to home reception.. It's FortecStar and other metal sheet dishes such as Famaval that flex in the wind: one strong gust can destroy a FortecStar 2.4m.

 

[neoandy]

you can have walls all round sheltering the dish.. so long as the angle up to the satellite is clear.. not as difficult with a prime focus..

you do lose on the joins.... another issue.. although there is one big join on the 2.4 CM...it's not a lot but it all adds up. you could put some ali tape or something over the join... but it might look awful..

btw..

both the 1.8 & 2.4 asc's are bigger in surface area than FS's... they are oval and their width is 1.8 / 2.4 but taller ... where as a prime focus is circular but the view by the lnb is considered the same (by some) in offset (it sees a circle of 1.8 or 2.4). I disagree to that as well as both the 1.8 & 2.4 (& 1.2 etc...) are all larger in catchment area that is reflected into the lnb.

We measure diagonally always to calc surface area .. ..You need to compare apples with apples.... surface area v surface area..

Anyway, it's usually a price thing.. £170 v £2600-£3000+ etc... but if one was to choose a Fortec Star ... it has to be put together very accurately, very carefully so not to buckle it ... use the right lnb /feed horn ...

......and when it's 100% .... seriously strengthen it with some diy engineering.

Many thanks again
About the join u said some tapes can be used over them ....does not afect the signal strenght if the tape is put over the dish in the reflecition area ?

Can the joins not be filled up with any kind of silicone material ( transparent for ex) ?

Cheers
Andy.

 

[guest poster]

You can flex a 2.4 CM with you arm, especially on the top panel... that's not to say they are like a floppy fortec, there is a lot of design in the face and they flex back, but they are not 100% rigid.. they are plastic with bracing and do 'give'.. they would have to be solid concrete not to give in a very strong winds at that size.. the bigger the dish the more they have to take.. and they are not really made for dth ..

as far as CM build quality - the face is good.. but I think the az/el is very poor. The crude threaded bar for the elevation and that daft azi fine adjuster... all rough dipped ... no bushes to take the slop on those holes.

 

[guest poster]

Many thanks again
About the join u said some tapes can be used over them ....does not afect the signal strenght if the tape is put over the dish in the reflecition area ?

Can the joins not be filled up with any kind of silicone material ( transparent for ex) ?

Cheers
Andy.

I think tape would look awful... I'm not aware of any silicone material that reflects microwave signals, but if the joins were siloconed you'd add some much needed extra strength but you'd have to make sure it was lined up 100% before it went off and you'd need a lot more strengthening than just that ....starting with remaking that er.. patio mount... bracing the panels .... a better elevation adjustment....

 

[divibi]

The tolerance is 0.25 inch or .6mm (max out) on the 2.4m's seam. The bolting procedure and torque settings are critical too, and if that's not followed either that can spoil a dish too. Very few have the equipment to test the parabola's tolerance of dishes that size.

Hi pedro2000uk

What equipment do you have in mind for testing the parabolic shape on dishes? Is it something 'optometric' or 'laser' based, that only small sizes can be done? I would love to know.

 

[guest poster]

Hi pedro2000uk

What equipment do you have in mind for testing the parabolic shape on dishes? Is it something 'optometric' or 'laser' based, that only small sizes can be done? I would love to know.

That sounds like a new thread....

How do you test the parabolic shape of an offset dish...

 

[dxsat]

Forget all about getting a FortecStar 2.4m to perform well- they just are not built well enough. The sheet material is so thin that it distorts easily.
I doubt the orginal poster and Neoandy are considering buying a 2.4 m ASC or Prodelin, so it's a bit a waste to talk about these. One-piece ASC or Prodelin 1.8m dishes may be in their price range and these are the best on the market by a long way. They do not distort in high winds by even a small amount. A well set up 1.8m dish of this type will out perform a FortecStar 2.4m easily, and this should be borne in mind above all the previous comments.

Offset dishes are more efficient than prime focus of the same size because:
- the larger surface area, as Pedro says, a 1.8m ASC is 1.9m high.
A prime focus '1.9m' Famaval is actually 1.79m x 1.79m working reflector area.
- less signal is blocked by support arms and feed owing to the offset design
- an offset dish is less susceptible to ground noise. The feed of a prime focus dish is pointing more towards the hot earth and will tend to pick up more noise, hence the design of a prime focus feed which tapers off reception towards the dish rim.
-prime focus dishes are much more difficult to set up owing to the shorter focal length. They perform much like a camera lens: anyone using a SLR camera will know that a lens set to F1.8 or 1.4 will be more difficult to focus than a F8 lens owing to the difference in the depth of field. It's the same with parabolic dishes: prime focus dishes have a very shallow point of accurate focus. No wonder then that many people on Costa Blanca suffer from bad reception, these dishes are the most common type used.

 

[divibi]

- an offset dish is less susceptible to ground noise. The feed of a prime focus dish is pointing more towards the hot earth and will tend to pick up more noise, hence the design of a prime focus feed which tapers off reception towards the dish rim.
-prime focus dishes are much more difficult to set up owing to the shorter focal length. They perform much like a camera lens: anyone using a SLR camera will know that a lens set to F1.8 or 1.4 will be more difficult to focus than a F8 lens owing to the difference in the depth of field. It's the same with parabolic dishes: prime focus dishes have a very shallow point of accurate focus. No wonder then that many people on Costa Blanca suffer from bad reception, these dishes are the most common type used.

good post! Thank you snap.

 

[guest poster]

The issue with the ground noise is wrong..

...that's come from wire mesh C Band dishes where it is true ....but it works the other way for solid metal dishes ....(er... not that solid in the case of the Fortecs).

Wire mesh reflects C band OK but lets x amount of noise through.... the solid metal KU band dish shields the lnb from ground noise and it just points up to the satellite...

The offset's lnb is then potentially more exposed to ground noise directly- it sticks out and aims across the Earth.

There are other issues that aren't right in you lists... I'm not biased either way, I've put people off the fs 2.4s before now and avoided doing them... but there's more swings and roundabouts that only a decent side by side test would give the acid test result....

I like the focus theory though. not sure it's right but I still like it.....

 

[dxsat]

All dishes of any type will receive noise from the ground, and surrounding buildings. This applies to Ku band as well as c Band. A good feed design minimises the amount of noise creeping in from the edges. You're right about cBand mesh dishes, but we are not talking about these.
Can't understand why you defend FortecStar dishes. They are complete cr*p. I'm a mod on another board and we have had more complaints about FortecStar dishes than any other, by a long way.
I have installed dishes professionally in Spain. I have been able to compare FortecStar 2.4m with other dishes side by side, as I bought one for myself. It lies rusting in my basement. No one in his right mind would think that these things can compare with a professional quality dish.

To the people asking about dishes in Costa Blanca: buy the best you can afford.
Some people in your area would like you to believe that "Portugese" dishes are the best. They aren't. The best LNBs for fringe BBC & ITV in Spain are made by Invacom. Don't even think about buying a FortecStar dish. Avoid buying anything from Maplin.

 

[guest poster]

I have to say you have come across with so many arguments that it comes across as obviously bias rather than an impartial technical view... a £2.500-£3000 dish should walk over a £170...

I wouldn't encourage anyone to buy one- especially not the 2.4, thinking they could just put it together like a cheap gazebo and then not strengthen them.. or I could see they clearly didn't have the skills needed.. and in either case .. I'd advise they'd be better getting a proper dish......

Looking at them from an engineering point of view ... if you address the problems and really set them up right (and without buckling them) and strengthen them as you do it, adding about £50-70 in materials to the 1.8 & about £80-100 to the 2.4 then they'll perform... but they'll look like a different dish..... So factor in that they just need re-engineering....it's just a parabola...

I also quietly admire from a production/ marketing point of view, that they can get a dish to the UK and retail so cheap..

As they are sold though... I wonder if they even conform to UK trading standard's definition of 'fit for purpose' ... as one good wind (draft) and they can end up floating around San Antonio harbour...

 

[neoandy]

Hi all of you ! Smashing work, being among all this info is just astonishing. I think is relly good to have so many points of in one row, i consider your opinin guys as a law, all of you agrees that the Fortec Star is not a good choice, as the quality does not reach the standards that we need out here in Spain to watch freesat.
I would like you to give me, if you can, prices of no so expensive dishes as ChannelMastrer, etc, and as well who sell them on the web.

I know that i been a pain, and i know that without money you cant do....but if there is not other option for dish i am gonna have to go and get one of this "Craptec Star" dish!
I know all of you agree that they are not good.....But as Pedro said before: I do not wanna be part of the "SheepFactor"......

Many thanks guys you are awsome....
Andy.

 

[yorks62]

First of all can i thank you guys as this forum as helped me no end in getting me set up down here in Benidorm with tv, I cant knock the fortec star dish, ok its a budget dish but its getting me bbc1 and itv right up till 22/23.00 hrs. Sorry to hijack the thread but can anyone tell me the strongest itv region signal for a free sat receiver ive just brought down from the UK

 

[woborny]

the ITV channels on 10905 v 22 5/6
ITV Channel Islands , Scottish TV, Ulster TV ITV 3

and 10758 v 22 5/6

ITV 1 London , ITV 2, ITV 4 , ITV 1 Granada TV , ITV 1 Anglia TV North ,
ITV 1 Central West

are nice and strong.. but it you have a sly card you can try and use those found on 12408 v 27 2/3 - but they may drop out during the afternoon but should be OK at night
ITV Mer SE, Thames South, Anglia West, York E, TTS, Central SW

 

[Huevos]

if there is not other option for dish i am gonna have to go and get one of this "Craptec Star" dish!

Why not just get yourself a 1.2/1.3m and low noise LNB if you are short of cash? You'd be surprised how much you can receive on it, including some of the vertical transponders on 2D.

Offset dishes are more efficient than prime focus of the same size because:
- the larger surface area, as Pedro says, a 1.8m ASC is 1.9m high.
A prime focus '1.9m' Famaval is actually 1.79m x 1.79m working reflector area.
- less signal is blocked by support arms and feed owing to the offset design

That's misleading. The dish may be 1.9m in height but the cross section offered to the satellite is only 1.8m due to the offset. Also the LNB shadow is not much of an issue. The area of the 1.8m dish is about 25,500cm2. The area blocked by the LNB/feedhorn is about 125cm2. That is not even 0.5% of the total area, and on a DB scale completely insignificant.

 

[joddle]

Hi all - up until last night I had a 2.4m fortecstar dish on my roof here in Valencia - Last night the 160km p hr wind took it away and folded it up for me so it wont be going back up very soon. However the question must be (according to many of the posts here) was it any good and fit for purpose?

Before I get into this we have to be fair - it was bloody cheap - and what was I really expecting for the price? I knew it would not be as good as a £700 solid dish - why the hell should it be? Its construction is a series of compormises - 6 petals instead of a solid shape and the accuracy of the parabolic shape varies around the petals fom the folded edge to the sheet centre - it is made of thin steel. There is virtually no support - the LNB arms are not very precise - The engineering is not very good - even the petal holes don't always match up......and there is loads more ---- BUT - it did work after a fashion - it was better than the 1.4 M solid dish that I already had - I could watch any freesat programme in the daytime no probs. It was in the night that its weaknesses really showed. Loss of BBC1 at 7:30 and no chance of BBC3 or 4 after 7:30ish - So was it any good? that is a matter of opinion - I would say it was good for the money - but not really up to providing what I needed here in Valencia - perhaps if I lived 100km to the norh it would have been perfect !! Its a bit like getting a cheap wheelbarrow when you really needed a dumper truck - ie it is only as good as it is - but that may be good enough fo some people in certain situations.

Anyway my Fortecstar is now pretty dead - and that is the real weakness of the dish - it is really very flimsy and therefore vulnarable to the weather - and that will be the case wherever you are never mind if its reception is good or not. I certainly won't be getting another...

SO - to all you people thinking of bringing a Maplin special to the Costa Blanca - my advise is DON'T - You should really be spending a bit more to get reliable reception - The agro is simply not worth it. But then again if you are a bit to the north of here - then - well its up to you..