Advice Needed Difference in Dish Size

[Riverblue]

I currently have a 1.0m Channel Master dish and I am looking to add a fixed 1.2m Channel Master for 7W. I was checking the specs on these dishes and noticed that the 1.0m dish is stated as having a gain of 40.5dBi @ 11.95 GHz and the 1.2m dish has a gain of 42.0dBi @ 11.95GHz, an increase of 1.5dBi. Does that mean that with the 1.2m installed with an identical Inverto Black Ultra lnb you would get an increase of 1.5dBi in the signal that is received by your sat box on a like for like basis with regard to stations/tps you are watching, or is it not as simple as that? I know that size is everything when it comes to signal reception, I am just trying to figure out how much difference the dish size will make to reception from this position re rain fade etc before I install the dish. The specific channels I am interested in I can already comfortably pull in with the 1.0m dish in good conditions. If it doesn't make much difference then I might go for a bigger dish, but I don't really want to if I can avoid it. Thanks for any replies

 

[timo_w2s]

I can't answer your question specifically, but when I had my 1.2m Channel Master with a Black Ultra single LNB temporarily on 7W in South Bucks a few months ago there wasn't a lot of room for rain fade on the transponders I could receive, so I would say 1.2m is a bare minimum. Of course it's probably slighter more in your favour being further south than me and it depends which channels you are after.

 

[archive10]

I currently have a 1.0m Channel Master dish and I am looking to add a fixed 1.2m Channel Master for 7W. I was checking the specs on these dishes and noticed that the 1.0m dish is stated as having a gain of 40.5dBi @ 11.95 GHz and the 1.2m dish has a gain of 42.0dBi @ 11.95GHz, an increase of 1.5dBi. Does that mean that with the 1.2m installed with an identical Inverto Black Ultra lnb you would get an increase of 1.5dBi in the signal that is received by your sat box on a like for like basis with regard to stations/tps you are watching, or is it not as simple as that? I know that size is everything when it comes to signal reception, I am just trying to figure out how much difference the dish size will make to reception from this position re rain fade etc before I install the dish.

The theoretical gain of the CM120 does not directly translate to gain on reception. But it will be in-the-order-of. It's relative to background noise, shape of dish, feed-horn shape / effeciency of the LNB / cabling etc etc. So if you have almost-there reception, the CM120 will do the job.

The specific channels I am interested in I can already comfortably pull in with the 1.0m dish in good conditions. If it doesn't make much difference then I might go for a bigger dish, but I don't really want to if I can avoid it. Thanks for any replies

So, if what you have works, don't change anything.
If you want to improve on rain-fade etc; get a CM120 dish face.
The CM100 and CM120 has the same mount, so it's a swap.
If I was in the UK, I'd offer you one I have, which is somewhat battered (and which I have no need for).
Have some bent arms to go with it; but it would allow you to experiment.
If you find a cheap one in the UK, get one, and just swap the dish with arms and all. You'll be happier...

 

[Riverblue]

So, if what you have works, don't change anything.
If you want to improve on rain-fade etc; get a CM120 dish face.
The CM100 and CM120 has the same mount, so it's a swap.
If I was in the UK, I'd offer you one I have, which is somewhat battered (and which I have no need for).
Have some bent arms to go with it; but it would allow you to experiment.
If you find a cheap one in the UK, get one, and just swap the dish with arms and all. You'll be happier...

I'm keeping my motorised 1.0m Channel Master setup as it is and adding a fixed dish (I have a 1.2m CM in the garage) for 7.0W. The reception I'm stating is from my 1.0m. Thanks for the kind offer of the dish though

 

[sonnetpete]

Riverblue : I have a 1M Gibertini as part of my multisat setup using a IBU at centre. The only transponders I have problems with are the older H ones that fade during the middle of the day. (I.E. Gear One on 12226H). On my 1.2M the only problems I have are when it rains and that has to be quite heavily. Bear in mind I am a bit further south than you (though not too far)

 

[Riverblue]

The tps at 7.0W that interest me are; 10853 H 27500 fec 2/3 8PSK, 11446 H 27500 fec 2/3 QPSK, 12245 V 27500 fec 2/3 8PSK, 12264 H 27500 fec 2/3 8PSK and 12475 V 27500 fec 2/3 8PSK. All listed as Eutelsat 7 West A mena beam. These tps will of course be very recognisable to some members;)

 

[RimaNTSS]

I am watching none of channels from 7*W. But bird is interesting cuz it is very weak and good for sat-equipment to be tested on. I just scanned it: Brussels, Fibo120, IBU, DM8000. Got signals from 56 transponders with average signal level about 59%
For comparison, marked green, I added signal levels I got couple of weeks ago in Latvia on 1.8m Prodelin with Fibo subreflector and IBU and same receiver. I would say, this satellite has quiet strange coverage patterns.