Remember this picture?
Look closely at the LNB with the feedhorn. Look familiar?
ZINWELL PLL LNB ZK-PF1G LN-139210 11.7 GHZ - 12.2 Ghz KU BAND VSAT
I could not find the matching waveguide feedhorn ;(
–Konrad, WA4OSH
Look closely at the LNB with the feedhorn. Look familiar?
I got parts coming to make a ups for the new setup but if the lnb needs power I wonder if there is a USB 5 volt adapter that we could use or will the new dream catcher board have the power supply built in?
We have removed the RTL-SDR, added a speaker, and also added a 2.4" QVGA display.
It works fine without the feedhorn. These LNBs are $20 used on eBay.
You don’t want the horn. We bought them strictly for benchmarking gain requirements. I think that particular horn was around $400.
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Yes, I saw the ZINWELL PLL LNB there on E-Bay. $400 for a feedhorn? Zow-wee. Yahh. I guess, in the 1980’s when it required a precise foundry and/or machining to make one. It won’t be long before manufacturing technology will be able to 3-D print these things out of recycled metal or metal-impregnated plastic.
–Konrad, WA4OSH.
Syed,
I am excited by the new more financially viable Outernet.
But this antenna and board is very different to the L-Band Outernet hardware.
What size of complete unit including feed horn, are you envisaging to offer the public?
How critical is it to aim the LNB antenna or will it work pointed straight up, as the L-Band used to in the Tropics.
Do you have L-Band versus Ku band antenna beam width comparison?
Will it, as a Ku unit be able to work whilst moving at 30kbps. ie Car Boat etc.(Which was the big attraction of L-Band)
What additional downloading content are you proposing for the 30kbps service?
Good luck with this new iteration. I will follow Outernet’s new journey with interest.
Seasalt
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That horn was bought from L3 new just a few months ago.
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Seasalt,
Me too! I’m quite excited by the new prospects of Outernet. And, yes, the new board will be different from the previous generations. I had an Apple Newton in the Early 90’s, before the Internet, before Wi-Fi, before Bluetooth, before PCS phones. I got silly looks from my managers in those days when I suggested that we would eventually want a cell phone that combines this tablet idea with a cell phone. I had invented one-touch dialing for cell phones a couple of years before and got strange looks and negative reviews for that idea. Sometimes it takes iterations to get things right.
When you are sailing near the Galapagos Islands, Inmarsat 4-F3 is right overhead. From here in the Seattle area (47.5deg North), the same satellite is right above moutain ridges and trees to the south. Of course, you will be pointing your tiny antenna straight up. I will be skimming the trees. 
Yes, the antenna can be put on a two axis and follow the satellite, just like the L-band dream.
If @Syed works this out right, maybe there can be one channel data and the other a mono audio program channel broadcasting a voice channel - music, talk, etc. With improvements in nano-material antennas, everyone’s antenna will be flat, solid state with no movint parts, completely self-steering and frequency agile. etc. Give this a half of a decade before it becomes mainstream and the cost is driven out of it. Programming will be much more diverse. We’re part of that revolution.
–Konrad, WA4OSH
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Okay, so from the reading I’ve done, there seem to be two types of Ku linear LNB’s, called Standard and Universal. The Standard type covers 11.7-12.2GHz, and the Universal covers 10.7-11.7 as the “low band” and 11.7-12.75 as the “high band”. Note that the Standard can’t reach above 12.2, but the Universal can.
All these units are intended to be bolted to a dish, so in order to receive both V and H polarized signals without the user having to run outside and twist the thing, they have an electrical means to select which signal probe in the feedhorn is active. This requires the receiver to tell the LNB a bit of information, and this is done with the power that’s superimposed on the coax.
The Standard LNB only needs to select polarization, so they do this with the power voltage. It’s either 13v or 18v, to select V or H, respectively. (And if you only need one, never switching, you can just source 13v and twist the unit until it lines up with the signal you want.)
The Universal type, on the other hand, needs to select both its polarization and its LO frequency. Two bits of data. So in addition to the voltage choice, the other bit comes as the presence or absence of a 22kHz tone superimposed on the power. Here again, the voltage selects the polarization, and the tone selects the band. High band requires the 22kHz tone to be present, for all the Universal LNB’s I’ve looked at. I think this is common across the industry. Without the tone, supplying pure DC, a Unversal LNB will only receive the low band.
Sooooo what? So, I need to know if the DC3 board can generate the 22kHz tone! If so, I can get a Universal LNB and be able to reach anywhere in the high band, including the 12.2-12.75 region that Standard LNB can’t cover. But if there’s no tone support, then I need to get a Standard LNB and hope the signal is always below 12.2, within its range.
Syed has said “Standard LNB”, but also “11.7-12.75”, so I’m a little less than certain.
Of course, I don’t want to merely receive Outernet, I also want to nose around this new band that’s caught my interest. (Who else might be packing data into DVB-S2 payloads, after all?) Which means I need a way to power my LNB and get the signal to my SDR. Bias tees are easy enough if I’m supplying DC, but if I need to superimpose a tone, I think it’s simpler to follow Gough Lui’s strategy and pick up a receiver with a loop-through port. The thinking is that a cheap FTA receiver will handle the LNB power and band selection for me, leaving me a simple loop output that I can pipe to my SDR. So with that in the path, I think I should be able do the needful with a Universal LNB, regardless of whether the DC3 will make 22kHz on its own.
My kingdom for a DIP switch. Oy.
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good info on using a “receiver” to drive the lnb.
this link refers to: (Satellite receivers have a tuner output port called Loop Out.)
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Yeah, we could always broadcast the blockchain on a separate channel, without the need for a dish. Though I’m not sure that it would be that useful…
How can you guys pick up the signal without a dish when they need one?
Shannon’s theorem of channel capacity is fundamental to all we do. It expresses how much information you can transmit over a channel with a given signal-to-noise ratio (SNR).
A dish (or any antenna that exhibits gain) helps you get more signal, and hopefully you’re able to position most of the sources of noise outside where you’re pointing it, so you also get less noise, improving your SNR two ways. The more SNR you have, and the more bandwidth (in the radio sense) you’re willing to occupy (MHz of spectrum), the more bits you can get through the channel with a given probability of error.
Which implies the inverse: If you’re willing to move fewer bits, you can do it with less SNR and thus less antenna gain.
And that’s how. 
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Just received the LNBF MK1-PLL along with suggested power supply. It has 2 F-connectors, input and output. I measure 20.5 volts at out connector, so this goes to LNBF. Just to get used to Ku band without a dish, I’ll use a RTL-SDR dongle and connect SMA to LNBF power supply F connector in. I’ll use SDR# for software, 20.5 volts out is for horizontal polarization. If I want vertical, I believe just twist LNBF 90 degrees? Wonder which satellite I should pick for US West Coast?
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Ah DC3! Used to ride in those birds in the far east… Air America
Interesting project indeed. Here’s a quick tutorial for blockstream:
Here in Seattle, I should be able to receive G18
By the way, this constellation diagram tells me the signal is QPSK.
Galaxy 18
TP 23 or 24
12178.43 H
? Symbol Rate
? FEC
The higher the symbol rate, the more link budget you need (It’s Shannon’s fault).
So I can understand why they need a 18 or 32 inch dish to receive it.
–Konrad, WA4OSH
I don’t have a problem with receiving signals with a raw LNB. The SCPC signal is much narrower than a whole TV channel. Therefore, the SDR can filter-out interfering signals a few KHz or MHz up or down from the carrier. It’s the same reason that SSB can’t compete with CW under noisy conditions – lower bandwidth. Yes, the sacrifice is a lower data rate.
@Syed I know you hate dishes … My only concern is that besides providing more link margin, larger antennas also provide narrower receive beamwidth and fewer side lobes. A dish antenna or feedhorn can eliminate interference from other neighboring satellite transponders on the Clarke Belt occupying the same frequency.
Konrad,
Do you think a SAW or BP filter would be useful right after the LNBF? Only while we are testing with a RTL-SDR. Most likely the new DC 3.0 would be built in. Also, it would nice to know the new Ku frequency very soon, so we can “tune-up” before the DC3 arrives. BTW the center frequency for the IF out of the LNBF is 1.200 Ghz
(950 + 1450) = 2400/2
Here is a very simple LNB block diagram…
Here’s a block diagram of an LNB for a service that uses RHCP and LHCP instead of V and H polarization. But the concept is the same. A universal LNB can switch the LO frequencies. Note that this block diagram is for Dish Network and DirecTV type Ku LNBs (the ones that Wikipedia does not mention).
Note that there are two Bandpass filters already in the receive chain, one before the LNA, the other one after.
Yes, I fully expect the DC 3.0 to have an SDR built into it. I also think it has hardware to decode complex modulations that are too difficult to do with a low-powered ARM chip eg. QPSK, 8PSK, 16QAM etc.
Yes and no. Judging from the new website that is up already, the product launch of the DC3 is not that far away. I’m probably going to concentrate on learning what’s on various satellites, especially what the SCPC signals look like.
I want to take a look at the various signals with GNU Radio Companion (GRC) on my Skywave Linux laptop.
I’m also considering getting a cheap DVB-S or DVB-S2 receiver and a small dish for FTA television to help aim a small dish at the satellite. Right now, I’m going to do the same with a Dish Network receiver and an 18 inch dish I was given recently. It’s all about learning about satellite broadcasting right now.
–Konrad, WA4OSH
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