INMARSAT Channels

[KJ4TDM]

@thebaldgeek

I recently got into INMARSAT's and have a setup running for 24hrs now, most of that time I spent in front the computer also. I live in central Alabama. I'll list my hardware below. I'm using a few different websites, yours included, for information on what I'm doing. Everything I'm about to explain is just me guessing with the info I have gathered.

I started out pointing my dish towards INMARSAT 3-F5 (from me 137deg 30deg elevation) but all I can really see is the marine channels, I use Scytale-C to decade those messages. I do see some other carriers but most are very weak, maybe some other satellite. Puzzled cause there should be a lot carries, I just started moving the dish around and settled on south west I see a lot of very strong signals. So now I think I'm looking at INMARSAT 4-F3 (from me 198deg 45deg elevation). This lines up with the app I'm using to find them. So now I start using the channel list from your site and others and find that the channels I'm decoding are form multiple INMARSAT satellites. Now I'm really confused. As I'm typing this up I'm hearing a doctor talk to a United Airlines flight that is off the coast of New Zealand which is under INMARSAT 4-F1.

What I started reading about this morning was about the coverage, specifically Global beam. Could that have something to do with what I'm experiencing? Which it looks like voice traffic is using Global coverage beam on all of them.

So if you can help explain / brake this down further it would ease my sanity. I have this problem where I pick up a new hobby and take it way to far until I master it then move onto the one. Thank for your knowledge and your website.

My hardware:
Nooelec Satellite Mesh Antenna Bundle for Inmarsat
Nooelec SAWbird+ iO
RTL-SDR v3

 

[thebaldgeek]

Glad you hear of another L-Band satcom station. Loads of fun (even though I don't do any voice).

If you look at the Inmarsat diagram on the bottom of the home page here: Node-RED Dashboard 2.0
You can see that from your location you only two sats visible: 4-F3 at 98w and 3F5 at 54w.
All others will simply not be an option, so that narrows things down a bit.

Let me Google that mesh antenna setup and see how likely it is that you are getting enough signal to get both from the one fixed angle.... Im sure some others here will be along shortly to add some input as well. We all started at one time or another.

 

[KJ4TDM]

Glad you hear of another L-Band satcom station. Loads of fun (even though I don't do any voice).

If you look at the Inmarsat diagram on the bottom of the home page here: Node-RED Dashboard 2.0
You can see that from your location you only two sats visible: 4-F3 at 98w and 3F5 at 54w.
All others will simply not be an option, so that narrows things down a bit.

Let me Google that mesh antenna setup and see how likely it is that you are getting enough signal to get both from the one fixed angle.... Im sure some others here will be along shortly to add some input as well. We all started at one time or another.

I seen the diagram and understand it. Just odd to me that I'm really only hearing 1 satellite very strong and the other is what it is. The screenshots below are form 3-f5. Maybe what I'm seeing is all that's there. I'm comparing it to what I see from 4-F3, major differences. Currently I have my dish on a tripod and just move it from one sat to the other when I want to switch. I hope to install it on my tower permanently at some point.