Is this dish ok?

[garyg]

I completely forgot I ordered this lol:

_http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=120600186462&ssPageName=STRK:MEWNX:IT

Hopefully it will come tomorrow then I can make the adaption to fit my dish.

Will that clamp allow me to move it forwards and backwards etc?

 

[pipino]

gary ,just a quick question...how are you taking the measurements??? are you trying the ADsport humax??

 

[garyg]

gary ,just a quick question...how are you taking the measurements??? are you trying the ADsport humax??

Well at the moment I am just playing around as I dont have a meter, I am using dubai sports as it has a lock.

I was getting 50% on dubai sports, I have moved the lnb to the other side of the bracket so it brings it back a little (its still over 1cm off what it needs to be) but signal is now 69% so it seems it is all in the lnb position.

So not alot I can do until my bracket comes, then il set it up properly (distance wise etc) And see what rolf can do with his meter.

No lock on Ad Sports tho

 

[Channel Hopper]

Another thought... how can i know when the feedhorn is pointing directly center of the dish?

Using a tape measure between feed centre and random points on the reflector edges gives a rough idea,
but a boresight tool is the way forward.
You can make one yourself, using a stiff rod, or a piece of 15mm copper pipe.
Another way is to remnove the feed cover off the horn and use a laser pointer. If you can score a circle on the reflector surface with the laser that is equidistant from the point where all quadrants meet up , then you are pointing directly down the centre.

 

[Huevos]

wtf is that black thing in the picture, the 3 ended thing!

It's an LNB holder off a Famaval 2.4 metre dish.

 

[garyg]

It's an LNB holder off a Famaval 2.4 metre dish.

I just pm'd you mate lol

 

[garyg]

I need to sort my lnb positioning out more then anything I think now.

Hopefully my bracket I ordered comes tomorrow, its recorded delivery so it should have come yesterday But lets hope tomorrow

 

[garyg]

Antenna diameter (D): 250 cm
Antenna depth (d): 37 cm
LNB distance to antenna (F): 105.57 cm
F/D ratio: 0.42

But that seems so much further out then the one that came with the dish??

Should I go with the above? Thats like 5cm further back then what i currently have the lnb :/

 

[Robbo]

Yes, but you have it a long way forward, much closer to the dish than shown in the iceman photo in the 2007 thread. The mathematical approach to knowing where the focus is, should theoretically be accurate, as it is based on the shape of the parabola. But in practice it will need to be found by moving in and out and finding the best point.

 

[Huevos]

Don't worry too much about the maths, as long as you make it fully adjustable all you need to do is move it in and out once the meter is plugged in and you will find the sweet spot.

 

[garyg]

Ok as soon as my new bracket comes il adapt it to fit and get rolf round!

Thank you guys lets just hope for the best!

 

[garyg]

Im nervous! lol.

What if I set the lnb up correctly and signal is still bad... what could it be?

 

[Huevos]

What if I set the lnb up correctly and signal is still bad?

Stop worrying, it's all going to work fine once it is adjusted.

 

[garyg]

Stop worrying, it's all going to work fine once it is adjusted.

Ok I take your word for it! LOL

For now, the football and a beer!

 

[Robbo]

You were getting it on the 1.8, you now have a dish almost twice the area, as long as it is illuminated properly, and you ae clearing obstacles, I don't think it can fail.

 

[Huevos]

You were getting it on the 1.8, you now have a dish almost twice the area,

It's equivelant to stepping from a 60cm dish to an 80cm.

 

[garyg]

I will have to hope my bracket comes tomorrow and go from there

I need to find an easy method to see if my lnb is pointing center dish

 

[wod]

regarding the lnb/ feedhorn bracket, what was on the dish originally cant you use this and mod it to fit the feedhorn you bought ?

 

[garyg]

regarding the lnb/ feedhorn bracket, what was on the dish originally cant you use this and mod it to fit the feedhorn you bought ?

We cant mate as its a completely different design.

Huevos has given my good advice on what to do with the bracket tomorrow when it comes and he seems to think it will work fine so we shal see! lol

 

[garyg]

Using a tape measure between feed centre and random points on the reflector edges gives a rough idea,
but a boresight tool is the way forward.
You can make one yourself, using a stiff rod, or a piece of 15mm copper pipe.
Another way is to remnove the feed cover off the horn and use a laser pointer. If you can score a circle on the reflector surface with the laser that is equidistant from the point where all quadrants meet up , then you are pointing directly down the centre.

I dont suppose you have any examples? I cannot find any info on checking its dead center