Bullseye LNB powersupply

General Othernet Discussions
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I am struggeling powering my new Bullsey LNB. As the power of my RTL-SDR via Bias-T is not sufficient,
I bought an external DC power modul plus attentuator.
However it looks as if the power provided with 12 V is too low. What is the best DC modul to be used?
My setup looks very much like this:

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my only recommendation is make sure you are inserting the power to the GREEN connector as described in the reviews by Testing the Othernet "Bullseye BE01" LNB

quote

  • DC power is tapped from the green coaxial connector via a real SMD inductor. Most LNBs get away with only a wiggly PCB trace; the BE01 has one under the large diode, but presumably this was not enough to protect the IF output from switching noise.
  • Unlike a standard Twin LNB, the BE01 can only draw power from one connector. Actually it is probably a good idea to refrain from applying DC voltage to the red connector; there is a resistive divider, but it is unclear whether it could handle 18 V from a set-top-box.
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There are a few on the market. Search for “qo-100 bias tee”.

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Thanks, although most of the shops here in Germany are closed, I was lucky and able to purchase a
power supply, providing 18 V and a simple power inserter (12€).
Works now fine.

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A bias-t is super easy and doesn’t really need much skill or measurement just ohm check to be sure there is no DC getting past the capacitor though I think even most RTL-SDRs have a coupling cap to stop DC from toasting the SDR, don’t count on that though. A bit of magnet wire around an iron nail(probably can skip the nail) makes a RF choke(inductor) to keep rf from going down your DC power wires, then most any ceramic disc coupling capacitor to couple the RF through while dead stopping the DC LNB power from reaching your SDR/radio/whatever. Just think a simple band pass duplexer where you are coupling 1GHz to your SDR and choking above DC down the power leg, easy.
Getting DC power over 12v easily is actually way harder if you don’t want to make or buy a clean boost power supply, those boost power things are super RF noisy, horrible harmonics can sometimes go pretty high and might mess with an IF even if you choke the crap out of the DC-out lines.
I guess someone could clip 2 9v batteries together 18v and use some zeiner diodes or maybe three to start at 27v and a switch between a 7815(add a resistor/pot to knock down to 14v) and a 7818 linear regulator to get your polarization, the LNB only pulls a few mA so the pbattery solution isn’t so bad for some quick experiments that is also SUPER clean DC other than stray RF in your shack, so shield and ground.

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I got the bullseye … it seems to work, comparable to the pll models i have…
i think a $12 is just as good, but I bought it support othernet !

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@ac8dg Thanks for the purchase and the support! Do you use this for FTA/TV reception? If so, yes, I don’t think you’ll notice any difference in signal quality. If it’s for Othernet reception, then there are a few LNBs that are stable enough.

The Bullseye was designed for very narrowband carriers. Most satellite tv channels are muxed onto 36 MHz carriers. Even smaller muxes are 8 MHz or so. The carrier we have for Othernet is 800 kHz. The carriers used on the QO-100 amateur radio satellite transponder are 2.5 KHz or even less. That’s where the precision of the Bullseye becomes useful.

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Who is selling the Bullseye LNBs on eBay and mentioning it as an Othernet design?