A Ku band sdr device

Is there an rtl sdr device that goes up to 10-12Ghz or are there down converters that exist?
If so, what are they called?
Thanks in advance.


No, I don’t know of any Ku-band SDRs. However, down-converters do exist. They’re called LNBs (Low-Noise Block down-converters).

The DC3 project will be based on a Maverick MK1-PLL. The LNBs are powered through the same coax that the L-Band signal comes down on. I bought mine from E-Bay. They also sell them on Amazon.

I use a Bias Tee to inject the DC voltage to the LNB. It wants 13 or 18 V depending on the polarity you select. The bias tee blocks DC from going towards the receiver.

[RTL-SDR]===RF===[Bias Tee]===RF+DC===[LNB]

I bought my Minicircuits Bias tee from E-Bay. I also made one. I can show you pictures and a schematic if you are interested. I power my bias tee with my lab supply.

The DC-3 project will include the Bias-Tee as part of its circuitry.

–Konrad, WA4OSH


I’d be interested in pictures and schematics. What frequencies would a mk1-pll bring ku band down to?

– Nate, KE0PFS

RF in is 11.7 to 12.2 GHz
IF out is 950 to 1450 MHz
LO is 10.750 GHz

I will take some pictures of things and draw up some schematics.

–Konrad, WA4OSH


So when tuning with a LNB. You just need to know by what factor.

I have a few rtl sdrs a few of them have bias tees. Although I think this voltage is to high for any of them .

So shopping list. Ku band antenna, bias tee, lnb.

Am I missing anything?

The factor (?) that you are referring to is the LO of the LNB. So if you tune to 950 MHz on the RTL-SDR, you are actually tuning at 950+10750 = 11,700 MHz.

No, your RTL-SDR may have a bias tee, but it can’s supply the right voltage to the LNB. It needs to supply 13 / 18v depending on the polarization. You will need a separate Bias Tee and maybe a lab supply. The voltages are used to change the polarity of the LNB - Vertical or Horizontal.

Be sure to buy an LNB with PLL frequency stabilization. The Maverick MK1-pll has been vetted by @Syed.

–Konrad, WA4OSH.


Here is my bias tee and schematic:

Surface-mount parts are really not that hard to work with. I took a small piece of two-sided FR4 circuit board and carved out the needed lines with an exacto knife. The back is solid copper. I ground the back with bare wire that connect front to back.

–Konrad, WA4OSH


Looks good,
What’s the inductance of the coil?


You caught me! (seriously, it was an omission on my part). I took a 100K Ohm resistor and wound some magnet wire on it that was in the junk box 30 ga? about 20 turns. I did not measure it. Typical values are around 1 nH. I don’t think it matters a whole lot.

I put it on a VNA and looked at the 21 (through) and 12 (reflected) and it looked ok. At VHF, UHF, and L-Band.

Here’s a Bias tee calculator that might be interesting to get better values.

–Konrad, WA4OSH

This Chinese one uses a tiny surface mount inductor L1 C1, C2 and C3 are similar. D1 looks like it’s for reverse voltage protection. It shorts out your power supply instead reverse-powering your LNA or LNB. I suppose R1 is a bleed-off resistor? Nice screw-on connector. The whole thing costs less than the SMA connectors on my board.


The point is that you can throw something together out of things in your junk box. I work with 1208 Surface Mount Devices because I can still see them and solder them onto home made boards by hand. I bought a grab bag of SMD devices for $5 at my friendly electronic store – Vetco

–Konrad, WA4OSH

Bias tee calc is what I need. Thanks!

I reckon I can cobble one together from pieces around my apartment.
So if I understand correctly, it’s a way of powering the antenna and removing the DC leaving only the RF from the output?

Time to dig out a bread board!

Switching from 13V to 18V won’t be necessary for the Outernet signal. Just twist (skew adjustment) once and you’ll be set.


@Konrad_Roeder Thanks! I’ve been meaning to pick up a selection of surface mount components, anyhow. I just need to remember not to go overboard on caffeine before soldering. rolls eyes

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So this service as oposed to the L-Band service would be impossible to use with a fixed antenna on a vehicle as the polarity would keep changing as the vehicle turned.

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The polarity does not change so much, the direction does. The polarity only changes a little when you move a large distance east or west (hundreds of km). Probably not even a problem in practice.


We are working on a circularly polarized antenna, as well. There will be a 3dB hit, but that would allow for no skew adjustment at all.

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I have my lnbf - mk-1, and a spare 90 cm off-set dish if needed, the feedline bias-tee,and an airspy.

Now… does anyone have a screen shot of what an SPSC or VSAT signal looks like? I have HDSDR and SDR# Sharp, I have found several continuous carriers in the 11.740 to 12.120GHz and a couple of wider double sideband waveforms as I point at various satellites like Galaxy 19.

I have an MK1-PLL, a modified 45 cm dish, a splitter that has DC pass on one side and DC block on the other. I have a dish pointing tool and a Freesat V8 satfinder. I also have a variety of RTL-SDRs including an airspy. My dish may be too small for me to lock onto a satellite yet, or I may not quite understand my setup.

Is the normal position for an MK1-PLL with the F-connnector facing down or to one side?

Which satellites are you looking at? Of course what I can see from Seattle may be just a bit different from where you are. Let’s go SCPC hunting.

–Konrad, WA4OSH

What’s the Frequency Kenneth? (Syed) :slight_smile:

A song by the American alternative rock band R.E.M.

Screenshot - 01232018 - 11:39:00 AM

I’m ready to receive!


Using my Freesat v8 satfinder, no splitter since it is providing the 13v, with the F oriented down and feedhorn pointing at the dish (got nothing w/o the reflector) I get signal ~75% but quality is tough to achieve. after programming in the transponders… I finally got a “blind” scan TV and radio channels at the 97W. So I disconnected the satfinder, hookup the “directTV” injector, and my NOOELEC rtl-sdr ( the one in the metal enclosure), then guessing at a frequency of 1,000Mhz after applying a 10.750G offset… I’m off to the races…

Edit: Now that I think about it, The directTV injector is supplying 21vdc vs the 13 v that the Freesat finder is injecting. So I may be comparing apples and oranges - or different polarities.

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