Getting Started with FTA

[Trip]

Mine is a signal issue. I checked it right as I went to bed last night and it had significant numbers of errors including moments of 0% signal. As of right now, the atmosphere is giveing me a completely clean LPB decode, but Montana PBS is completely gone. No OETA either.

I didn't realize atmospheric conditions would cause satellite signals to vary this much. I mean, I knew about rain fade and whatnot, but it's not raining or even cloudy.

- Trip

 

[SatelliteAV]

Scanning through this thread, I assume that you are still using the used 30" dish?

If so, this size of dish is marginal for many MPEG2 signals and definitely undersized for reliable MPEG4 signals with typically higher FEC. The higher the FEC, the more critical that the receiver is provided a signal higher quality signals.

Have you performed a string test on the reflector to determine if it may be warped? A combination of an undersized reflector and even the slightest distortion of the dish could result in reception problems.

My guess is that a 90cm dish would provide more reliable reception.....

 

[Trip]

Yes, I've not replaced my dish, though I've been trying to keep my eyes open for something larger in the area. I kept thinking my current one was 90cm, but just redid the math in my head and realized that 90cm is 36 inches, not 30 inches. Oops. I'll likely have to find my way to another hamfest to have any chance of finding one without buying new, however. (Plus a larger dish means I would need to replace my mast for sure, as the current dish almost touches the ground as it is.)

I'm unfamiliar with a string test, but it would not surprise me in the least if the thing was warped or damaged in some way. I just looked up how to do a string test and it seems simple enough, so since it's supposed to be another reasonably nice day today, I may run out and give it a try. Depends on what else I do today, of course.

One other thing I tried yesterday was swapping out the LNB that came with it with the one I bought on eBay back in February and had used at school. The one that came with it was significantly better, so I put it back. The one I bought had a 1 dB NF while the one that came with the dish claims 0.6 dB NF, but I can't imagine that's the whole story.

- Trip

 

[SatelliteAV]

One other thing I tried yesterday was swapping out the LNB that came with it with the one I bought on eBay back in February and had used at school. The one that came with it was significantly better, so I put it back. The one I bought had a 1 dB NF while the one that came with the dish claims 0.6 dB NF, but I can't imagine that's the whole story.

Please share the brand and model of the LNBF with 0.1NF that does not perform as well as the old 0.6NR.......

The over exaggeration of performance is called marketing hype! The LNBFs that we have tested that claim 0.1 or 0.2NR are actually 0.8 or higher!

 

[Trip]

It claims 1 NF, not 0.1 NF. It is a DMS International JSC321S. I got it for $10 on eBay before I really knew what I was doing. Knowing what I know today, I'd have gone with something else.

I also have this DirecTV LNB here that I've never used, and I have been puzzling over whether or not I can use it as a circular LNB for the Echostar satellites somehow.

- Trip

 

[SatelliteAV]

Actually that model LNBF model specifications are advertised as a 0.3dB NR. Several popular brand LNBFs were recently tested at 0.7dB+ NR during comparison testing by our manufacturers contracted lab.

Perfect examples of current advertising hype on NR and Gain. Seems that it is easier to print a spec than it is to meet a spec......

 

[turbosat]

I have a couple of those 321 lnbfs, for several months now. Seem to work very well for me, but I'm not trying to get S2 with them either.
Does just fine on a 90cm Channel master (primestar) dish. I put one on a DN 20" dish, for that little project, works great in clear weather.
Which is all we're having these days , no rain in nearly 4wks.

 

[SatelliteAV]

Totally agree that the product works fine, but they definitely are not 0.1dB NR. Just a typical off the shelf LNBF. Trip has an issue with his system that won't be addressed by a few points gain on an LNBF.

Trip, Are you only using high quality RG6 coax cable with minimal connectors or splices?

 

[Trip]

I'm using a single 150 foot run of RG-11 to a piece of cheap flat coax that I'd prefer to be rid of but that I need to get the cable through the window, and then there's about 5 feet of RG-6 connecting the flat coax to the receiver. The motor is connected to the LNB with a short run of RG-6.

Maybe someone can explain what I've been observing. I spot checked the three S2 PBS feeds throughout the day. What I found odd is that all three would not come in at once, and there seemed to be no consistent pattern. At various times I got clean decodes from LPB or Montana (but not both) and sometimes I got OETA but with breakups. I'm used to OTA DX, where you might have a "beacon" signal that comes in first and then others follow it and then they fade out in reverse order, but there was nothing like that in this case. Sometimes Montana would be clean with OETA breaking up and nothing from LPB. Other times, Montana would be in while LPB was broken up and OETA was missing. Sometimes LPB was perfect and Montana and OETA were completely absent. Sometimes all three would be in and broken up. Is there a technical reason for why this seems so inconsistent? I can't find any pattern to why they seem to come and go in a seemingly random manner.

- Trip