New norsat 8115
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Yeah...I have a new 8115 coming! I hope this helps me lock some harder to get s2 feeds!
I hope you have better luck than I did. I upgraded from my OLD Cal Amp (I think) lnb that had a freq stability somewhere in the 750-1000 KHz range, to an 8115 a year or so ago, with the same intent. I thought that the better freq stability (I forget exactly, but I think the 8115 is around 100-150 KHz). Well, despite the fact that it was a much more stable lnb, I couldn't lock a lot of transponders that I WAS able to lock with the old Cal Amp. I think it's because the old LNB had a bit more gain, and the Norsat must get it's freq stability at the expense of a bit of gain.
In MY case, I was trying to compensate for a dish that is in extremely poor condition (all sorts of dents, and it's warped, etc) with a higher quality LNB. It didn't work. I ended up taking the 8115 off the dish, and putting my old Cal Amp back on. If I ever get a new dish, or am somehow able to fix the dents in my dish, I may try the 8115 again, because I DO think that it is a quality LNB, but I've decided that dish quality is MUCH more important to DVB-S2 reception than LNB quality is, and at least in my case, gain is more important than stability.
Good luck, but just wanted to prepare you for the possibility that the better LNB might make things worse.
Modern receivers generally have a wide lock range, so a high frequency stability LNB is normally of little value unless one is trying to lock very low SRs. I've tested entering the wrong frequencies into all of my receivers, and they can readily capture signals 5-10 MHz off. Still, I like my signals to show up at the correct frequency on my bench spectrum analyzer, so I happen to use 8115s.
What 8115s really have going for them is very low phase noise for a DRO LNB. That might help lock S2 signals better than a crummy LNB with poor phase noise specs, but I read a study recently that seems to indicate the value of 8115-level phase noise specs would be more important for 16PSK and higher.
As to the Cal Amp vs. 8115 gain issue, are there a lot of losses in your distribution chain following the LNB? If so a low gain, high quality amplifier at the LNB might help. I finally got my 3.2m up last week and put some 8115s on it. I'm guessing there's about 200' of cable between the LNB and receiver, and some switch losses along the way. Now admittedly a tweaked 3.2 has tons of signal, and without any amplifier in the chain I was seeing better SQs and SNRs than I ever had before on my 3m. However when I looked on the spectrum analyzer, I noticed the potential for a little noise combining on the receiver side. I ran out and installed a Channel Master amp near the LNBs and the SQs shot up another 4-5 points. It's going to stay.
One thing that has piqued my interest at times, but not enough to do anything, was the question of how well LNBs match a particular feed. I don't have anything to offer, but it might be the Cal Amp simply works better for that feed. I'm pretty happy with my 8115s so I don't have a big drive to do it, but I had thought about trying different LNBs on all the different kinds of feeds I have, and possibly on different dishes to see if there is any correlations I could draw. That would certainly burn up some time.
Regardless of all the above, you are correct that S2 is going to put a premium on dishes in decent condition.
I took a peek at the Cal Amp specs. The 140105-1 is DRO like the Norsat 8115 with a poorer frequency stability (500 vs. 100 KHz), but much better phase noise specs (-73 vs. -65 dBc/Hz @ 1kHz, -95 vs. -80 @ 10 kHz and -110 vs. -95 @ 100 kHz). One might question some LNB suppliers over specs, but these are both reputable manufacturers and the differences are not small. I'd have to do some math to see whether this would improve 'lockability', but it sounds interesting. Are there any good Cal Amp suppliers?
I bought Cal amps from here before:
Vincor Limited - Earth Station Antenna and Satellite Communication Product Specialists
Yeah...I have a new 8115 coming! I hope this helps me lock some harder to get s2 feeds!
I've been "eyeballing" this LNB, also, since my much older, "standard freq stability", Norsat doesn't lock the S2 stuff. (I'm too lazy to go out in the rain to check the model number
). I'd be really interested in hearing how it performs for you.
Someone isn't paying attention to their descriptions and pricing on their website. They talk about the Corotor II+ Wideband under the Corotor II Plus and they show a list price for the Norsat 8115 as $119 with their price as $189.
Installed my 8115 today. Its rainy and stormy here today so my observations could be flawed.
My 91w c band signals went up a little, while most signals across the arc are unchanged.
The one thing i do notice is the signal quality is very smooth and not jumping up and down on most transponders. So i guess my little cheap dmsi bsc 211 13 degree lnb was not terribly bad using norsat as a reference.
My 91w c band signals went up a little, while most signals across the arc are unchanged.
The one thing i do notice is the signal quality is very smooth and not jumping up and down on most transponders. So i guess my little cheap dmsi bsc 211 13 degree lnb was not terribly bad using norsat as a reference.
Bummer. I wonder if a PLL LNB would be any better. PLL is a bit more money than I'd like to spend but if it gives me the performance I need for S2 then I guess it'd be worth it. But first, I need to get my L bolts so that I can pour the concrete pad for my new 12' dish. I got a 4' deep hole in the ground waiting. I'll have to call the local shops and find out why they haven't called me with quotes for the L-bolts yet - I might just go ahead and special order the box of 10 bolts (minimum quantity) if these people don't want my business. Hopefully, I'll get this done before winter gets going - no hard freeze here yet and none in the 10 day forecast. Anyway, I'm going to see what performance I get with my current feed and LNB's, first, before spending more money.
I can tell you the improvment was nor 100.00 worth imho.
Now a high quality lnb may last for many years vs a cheapo. I have already had a cheapo fail after a year - but i only paid 12.00 for it off ebay. So changing one per year you would be out 120.00 over 10 years LOL.
Now a high quality lnb may last for many years vs a cheapo. I have already had a cheapo fail after a year - but i only paid 12.00 for it off ebay. So changing one per year you would be out 120.00 over 10 years LOL.
I've been "eyeballing" this LNB, also, since my much older, "standard freq stability", Norsat doesn't lock the S2 stuff. (I'm too lazy to go out in the rain to check the model number
FTA S2 locking is determined far more by phase noise than frequency stability. The Norsat 8115 has good specs for both and will not be the limiting factor for typical S2 SRs. Unfortunately it is hard to compare phase noise specs for older and low cost LNBs because they normally are ill-specified. While you might get a few tenths of a dB improvement with an 8115, I would expect that alignment and dish size are more typically the fail-to-lock reasons in most systems.
If you want the best chance for S2 locking, I would suggest a single orthomode feed. The losses are less than for a dual ortho and much less than a rotor. With a single ortho and 8115s, I can lock a fair fraction of the available S2 on my 1.8m. The 2.3m does nearly all, and the 3m never even breaks a sweat. I haven't had a chance to test my new 3.2m on much S2, but it's doing obviously better than the 3m on what I have tested.
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