Inmarsat Software Defined Radio Books

A subreddit for the low-cost, DIY software defined radio (SDR) community. While originally dedicated just to the project, relevant legal content related to general SDR, RF and similar projects is also welcomed. Feel free to ask questions but please.

Rtl-sdr 'rtl-sdr' is a generic term for cheap USB digital TV (DVB-T) receivers that use the Realtek RTL2832U chipset, which can function as general purpose software defined radios (receive only). All rtl-sdr compatible devices employ the RTL2832U as an ADC and USB controller, but different RF tuners may be used. Note that rtl-sdrs do not transmit! Typical specs (some depend on specific tuner): • Cost: ~$5-45 USD • Frequency range: 24 - >1760 MHz (100 KHz - 24 MHz in direct sampling mode) • Max sample rate: 3.2 MS/s (2.6 MS/s in practice) • Resolution: 8 bits/sample • Noise figure. I'm using an 18in.

Look at most relevant Inmarsat c for mac websites out of 73.5 Thousand at KeyOptimize.com. Inmarsat c for mac found at inmarsat.com, books. Software defined radio.

DirecTV (it's actually Bell ExpressVu but force of habit) dish with a LHCP helical feed point (I was under the impression that the polarity reverses from RHCP to LHCP after it hits the dish and 'reflects' into the feed point) cut for 1537.5mHz.. I've tried a rough pointing (without a signal meter) just using ARDishPointer for iphone, some of the websites online + a compass but so far as I can tell I'm not able to pull anything down. I have a friend who has an analog signal meter coming through this weekend so I might be able to get a more solid pointing My biggest concern is the proper placement of the helical feed point, I'm assuming that it's position would be different than that of the original LNBf so that it would be able to hit the focal point of the dish, correct?

Also, is there a certain control frequency or frequencies that are always on that I could use to tell whether I'm hitting the satellite? If so, it's in upper sideband mode?

I've ordered a and I'm hoping that may alleviate my troubles but any tips from someone who has done this would be appreciated. And yes, I've seen the Youtube videos and yes, I know the guy who made them is a redditor, but he was last active about a year ago and I'm not sure if he'll respond to my PM. FYI, I use a Funcube Pro+ and RTLSDR, no difference in results edit: I'm pulling something down on 1.974gHz but I'm not sure what. At least I know my feed point works. I just have to say I'm shocked that there's anything still on the Inmarsat system that can be decoded by hobbyists. I was obsessed with receiving Inmarsat back in the year 2000 or so but didn't have the equipment back then.

As far as the antenna goes: how are you pointing the dish, exactly? Those little dishes use an offset feed, so their beam isn't straight out of the center like a prime focus dish. I assume you know that already, though.

Also, I wouldn't worry too much about the exact forward/back placement of the antenna at the focal point. I've found that to be one of the least critical adjustments for dish alignment. If you can find something you think might be an Inmarsat signal, just move the antenna in and out a bit until you find the point where the signal is strongest.

I wish I saw this a week ago. I ordered an Amsat preamp that covers 100-500 approx. So if I can get away with a 1-2gHz Narrowband, I assume it would be better than working with an wideband LNA as the narrowband would be designed and tuned for that 1-2ghz chunk I'm looking for, right? Most of the stuff between 500mhz-1ghz that I have any interest in working with is terrestrial so while it would be nice to have some amplification on those signals, it's not entirely necessary for me.

However, I'm basing this all on my hope that the Amsat preamp will do well. If it's garbage then I might reconsider because you don't beat that price. I think its likely that the Amsat preamp will turn out to have a much wider usable range than is advertised. I am sure it will work well, I mean, look at who they are. Yes- for some kinds of work, you MAY want some selectivity in the front end. You can also build some selectivity into your input stage. Data Warehousing Data Mining And Olap Alex Berson Pdf Compressor. As far as LNAS go, there are cheaper ways to do it (than Adams) but you would have to build a kit.

Seems to me that doing that you could easily not do so well. Adams other projects are on the web at and the workmanship he puts into them is clearly excellent quality. He's been very helpful in also giving me advice on how to do various things. He's basically a really nice, knowledgeable guy. And his LNA is a great deal. The two similar '5043' chips cover the entire range of frequencies that the RTLSDRs cover.

(Which is actually, I realized, isn't so easy for a single device) They both have excellent low noise performance and high IP3. Enough to have impressed a lot of people whose opinions I respect. Also, the PSA4-5043+ (and perhaps the RFMD chip too), has built in ESD protection. I have been using the Minicircuits chip and I've not fried a single one yet. Some of them have been reused two or three times as I've gotten better at it. If you are using it with the RTL-SDR you may want to read the page here about noise figure, also The useful ability to tweak the way the e4000 divides its work between the e4000's internal stages is not in the rtl-sdr from osmocom yet, I don't think. But I could easily be wrong, I have not updated my rtlsdr in at least two months so I don't know.

There are some measurements here (scroll down) which compare the NF of a bunch of LNAs, including the psa4-5043+ - The others are moonbounce LNAs. Ive asked several 'experts' whether its worth the effort to try to get a still lower NF - Basically, what I gathered was, no, it wasn't for me. It might be for you, but right now, its not something which would make any more difference for me. It is 'possible' to eke out another 0.4 db of noise figure - but as doing that is a PITA unless someone is doing space work, there is no way to make use of that improved NF, because of the inherent noise of the ground around us. Basically, you would need to have your directional antenna pointing up at the cold sky.

To make the best use of an LNA, it should be mounted right on or near, your antenna. Once you get your preamp, which ever one you decide on, or both (If you keep your rtlsdr indoors, and use a long cable run, you may need more than one) whatever, then you will find that it works, and is a huge improvement. Then, if you are like me, you will probably sit there and say to yourself 'Okay, that was the easy part, now to get better reception, I'll need to improve whatever antenna I'm using.

I think its likely that the Amsat preamp will turn out to have a much wider usable range than is advertised Interesting, what do you base that off of? I hope you're right but when I asked about it in some Yahoo groups, even the VP of Amsat didn't sound too enthusiastic about it's capabilities but I'm hoping he was just trying to undersell. I don't know. As far as LNAS go, there are cheaper ways to do it (than Adams) but you would have to build a kit. Seems to me that doing that you could easily not do so well.

I would 100% want something pre-assembled if I can get away with it but some of the prices compared to the kits are astronomical. I don't know the first thing about assembling PCBs and the like but from what I've seen, if I really needed to and had a decent reference/somebody who knew what they were doing, I could learn. It'd be a matter of getting the right tools for the job I guess. As far as Adam's LNA goes, I may possibly have a trade with another redditor for one of those units but if it falls through I may just pick one up.

BTW, I find myself using the Funcube Pro+ more than the RTLSDR for alot of things and the FCD has a built in LNA so I'm not even so sure if any LNA will help at this point but for the price it's worth a try. I have a 'deep' perfectly spherical 32 cm pot lid that I bought at the incredible in San Francisco and although I don't think it can produce 'dish like' gain at 2400 MHz it definitely does increase the gain of any antenna that is put in front of it substantially. It also can focus light to a blinding point (its an absolutely perfect parabola) How much gain does it add at these low frequencies? For GPS and 1090 MHz it is probably no more than 6 or 9 db. The sticker on this pot lid says the price was $5.29 which sounds about right. It is far superior to a wok strainer for wifi;) I attached it to the shell of a clip on fan and I have a PVC pipe going through the hole for the handle, it looks quite professional, considering what it is. The direction is completely adjustable.

If any of you are in San Francisco I highly recommend Kamei for all your kitchen stuff. They have everything you could ever imagine. That neighborhood, the inner Richmond also probably has the most GOOD restaurants per block of any neighborhood in San Francisco, (which means the most in the whole US!) They have every ethnic cusine you could ever imagine. The competition there must be huge.

A subreddit for the low-cost, DIY software defined radio (SDR) community. While originally dedicated just to the project, relevant legal content related to general SDR, RF and similar projects is also welcomed. Feel free to ask questions but please. Rtl-sdr 'rtl-sdr' is a generic term for cheap USB digital TV (DVB-T) receivers that use the Realtek RTL2832U chipset, which can function as general purpose software defined radios (receive only). All rtl-sdr compatible devices employ the RTL2832U as an ADC and USB controller, but different RF tuners may be used.

Note that rtl-sdrs do not transmit! Typical specs (some depend on specific tuner): • Cost: ~$5-45 USD • Frequency range: 24 - >1760 MHz (100 KHz - 24 MHz in direct sampling mode) • Max sample rate: 3.2 MS/s (2.6 MS/s in practice) • Resolution: 8 bits/sample • Noise figure. Hi all, Last couple of days I have been playing with Inmarsat L-band stuff. I can now confirm that I was receiving signal from satellite at 64 East (I thought it was sat at 24 E).

This was result of very scientific 'antenna in a steel bucket' -procedure. I put the antenna into bottom of a bucket and by panning left and right certain signals were fading away when others came in stronger.

The gain of bucket feed horn is same as cooking tin, but it's now more directional. And as result I can see, that there's only three Classic AERO channels on 23 East (nine at 64E) and pretty much none STD-C (marine info channel). But this is a good start. Next step would be helix antenna and LNA4ALL amplifier.