Dish Sizing Questions

[Signa Lawst]

Hi folks.

I'm new to Sat. technology, and have the intent to install a dish for myself. I'll be aiming at the Anik F1 satellite, and need to size my dish appropriately.

Most (normal?) Anik F1 subscribers (Star Choice) are able to use a subscription provided 24 inch dish. They are, for the most part, miles to my north. My pointing angle to Anik F1 at 107.3 west is Azimuth 199.4 degrees, with an elevation of 37.5 degrees off the horizon. A 3rd party dish retailer suggests that I should have a larger dish (any) for my location in Minnesota, and that the need for a larger dish increases as one goes south.

Here's my mental dilemma. I believe I understand correctly that an azimuth of 180 is directly south of me and that 199 would be on the west side of south. I also see from aiming charts that the further south I go, the higher the degree of elevation is. To me, this means that as I travel straight south, I get closer to the satellite for some amount of time until the satellite is as directly overhead as it will get at my longitude.

So if I'm getting closer to the satellite, why in the world do I need a larger dish, outside of a generic "bigger is better?"

Am I just lining the dish retailer's pockets, or am I wrong about my concept of azimuth and where that satellite is in comparison to my location? I won't be surprised if it's the latter...

Thanks!

 

[Signa Lawst]

Welllllll. Frankly I'm a bit surprised, here. Just about a week later, there have been 90+ views of this topic, and it's likely that most of the 90 are forum regulars. Not one response.

This has to be a very basic question about layer one satellite provisioning. Are the local forum patrons too shy to comment? Did I stump the panel with this? Did I forget to add the secret satellite club handshake?

90 people. Not a ONE of them to either confirm that I'm correct, tell me how I'm looking at this wrong, or at the LEAST say, "Ya know...that's a great question, and I don't know the answer! Maybe one of the 'professionals' who lurk around here spouting off all sorts of advanced looking satellite infobits can answer this."

Or hey...tell me to give up and take a hike?

 

[dfergie]

Welcome to SatelliteGuys!, I'll move this to the Canadian section.

 

[pendragon]

The antenna on Anik F1 is centered on Canada, so the farther south you go, the less power you will receive. But for MN, 90cm should be fine. On dishpointer.com, I get a true azimuth of 196 degrees and an elevation of 35 degrees for Rain Forest, MN.

 

[alexcast]

Get the 75E 75 cms elliptical dish and you won't have any problem getting 107 and 111

 

[Mr Tony]

I'm new to Sat. technology, and have the intent to install a dish for myself. I'll be aiming at the Anik F1 satellite, and need to size my dish appropriately.

Most (normal?) Anik F1 subscribers (Star Choice) are able to use a subscription provided 24 inch dish. They are, for the most part, miles to my north. My pointing angle to Anik F1 at 107.3 west is Azimuth 199.4 degrees, with an elevation of 37.5 degrees off the horizon. A 3rd party dish retailer suggests that I should have a larger dish (any) for my location in Minnesota, and that the need for a larger dish increases as one goes south.

correct. Since there is no place as "Rain Forest, MN" maybe you mean Forest Lake. I've lived in MN 35 years and Rain Forest sounds like a mythical place (like places men fear to tread)
By the way I'm in SW suburbs of Mpls

Anywho..as noted above the footprint of the satellite (the sweet spot) is over Canada. Don't get me wrong. the 60e dish (32x18) will work in Minneapolis. I did an install about 4 years ago for a guy in Eagan area and had a 60e. The issue is the signal is pretty low and any dark clouds or rain will kill the signal. It also wasnt the easiest thing to aim

The 75e dish is 37x27 and works great. Done a few installs for folks with those dishes. Way easier to aim and peak to get optimum signal

Here's my mental dilemma. I believe I understand correctly that an azimuth of 180 is directly south of me and that 199 would be on the west side of south. I also see from aiming charts that the further south I go, the higher the degree of elevation is. To me, this means that as I travel straight south, I get closer to the satellite for some amount of time until the satellite is as directly overhead as it will get at my longitude.

So if I'm getting closer to the satellite, why in the world do I need a larger dish, outside of a generic "bigger is better?"

you arent getting closer to the satellite per say. The satellites are at fixed locations in the sky (known as the Clarke Belt). The location of the sat is at a fixed longitude. Anik sats are at 107.3 & 111.1 West longitude. In Minneapolis we are at 93.5W so we're close. Over in Colorado they are around the same longitude so the dish is aimed higher.
The closer you are to your true south satellite (the satellite at the same longitude as you) the higher in the sky the dish is aimed. That is just normal

So if I wanted to aim a dish at 93W the dish is at the highest for us (38.4)...That is why Directv dishes are aimed higher that Dish dishes

As I noted above, both dishes will work here in Minnesota but the 60e will go out when it rains

 

[joshuals]

Or hey...tell me to give up and take a hike?

Naahhh...you were just in the wrong forum....hopefully you have found your way here now.

My pointing angle to Anik F1 at 107.3 west is Azimuth 199.4 degrees,

Since you say you are new at this, please be sure you understand the difference between True North and Magnetic (Compass) North. You need to know whether the Azimuth that you cited is referenced to True or Magnetic, then act accordingly when you use your compass to rough-point the dish. Several posters who were not aware of this spent a lot of time trying without success to find the satelllite signal. If you need more info on this, please say so. A good source of instruction on getting up & running with Shaw can be found on KuSat's website.

Also, be SURE that the mast for your dish is plumb before mounting the dish to it. If the mast is out of plumb, your dish for elevation and skew will be wrong, even if they appear to be correct on the dish itself.

Good luck.....

 

[bradleys]

You should definitely install a larger dish. Other posters have recommended the 75e, and I agree. That's what I have in Port McNeill BC and Seattle. It's very easy to aim and get a good signal. It's not sensitive to minor movement like wind (or waves or dock movement in my case).

 

[pendragon]

Strike my comment about the 90cm dish. I must have misread the original post. Sorry.

 

[Mr Tony]

a 90cm will work fine for one satellite but can be a bugger for both since they are 3.8 degrees apart.

I was able to do both sats on a 4 footer because of the spacing being different. There was a bigger gap due to the focal spot

 

[pendragon]

I also ended up using a 1.2m for both birds, but mostly for better rain fade margin on 111.1 in Colorado. The two LNBFs I used nearly touch when set up for the SD satellites.

My 1.2m has a fairly low f/D of 0.5, meaning the focal length is 0.6m. That's the same as a 1.0m with a more normal f/D of 0.6, and fairly close to a 90cm with a 0.6 f/D. Because the focal length determines the separation between 107.3 and 111.1, all three of these combinations would be within about 0.2" in LNBF separation. Depending on the size of the LNBF scalars and caps, that may or may not be meaningful.

 

[Mr Tony]

yeah mine is about the same when I had the 4 footer up for Shaw
SatelliteGuys.US - View Single Post - DSR505 Ebno #'s on HD channels low??

 

[mellaby]

I winter in Mesa AZ and I use a 60cm dish. It works great except on HD when it's a heavy rain. Maybe your weather up in MN is worse. I tuned up a few dishes down here and the 75cm has much better signal strength on the HD channels. The problem is trying to find a good price on a 75cm dish.

 

[Signa Lawst]

Excellent information, all. I've got some digesting to do.

 

[joshuals]

I recently priced a 75e at $99 from a Canadian vendor, but the cheapest freight was about $125.....

I winter in Mesa AZ and I use a 60cm dish.

With the number of Canadian winter visitors in that area, have you tried any garage sales for a 75e?

I'm on the opposite of side of the Valley where we also have a healthy population of snowbirds, but no luck at garage sales after 3 years of searching......

 

[mellaby]

For $99 from a vendor, I would be better to signup for the Home Away from Home program at SD. It's $100 and they send you a 75cm dish.

 

[QCK]

For $99 from a vendor, I would be better to signup for the Home Away from Home program at SD. It's $100 and they send you a 75cm dish.

That is only a good option if you have someone living at your Canadian address and you then have the ability to get the dish down to your southern location.

It's a one time deal, the box is very large and if you can afford to live in the south you should be able to afford $125 for shipping IMO.

 

[mellaby]

QCK - I should have said I'm a Canadian snowbird. I can register now @ SD.

 

[QCK]

That's perfect then, all you need is proof of your US residence (tax or utility bill faxed to them) and they will send you the 75E dish to your Canadian residence.

 

[Signa Lawst]

First off, thanks to all who replied, and Iceberg for pointing out the sweet spot concept.

I believe I have finally grasped this by likening the satellite to a can of spray paint, and understanding that I need my bucket (dish) to catch a certain required amount of paint per second to fill my TV easel. Probably a horrible analogy or laughable at any rate, but it might help other newbies to think of it this way some day.