Input on Enclosure Made from Dry Box (similar to an Otterbox)

Another layer of plastic definitely attenuates the signal. This is a good idea for stability purposes and also to remove an additional part from the assembly (the LNB holder). But in order for this to work, the LNB would need to stick out of the end of the box.

Yeah, that is an option. But I’m hoping for something that doesn’t appear too hacky. I know this case won’t be the most elegant of enclosures, but bolting parts on willy-nilly makes it a harder sell for non-hobbyists.

We’ve had it running inside of a clear, greenhouse-like container for months on end. 120F/50C operations were fine, but I can’t vouch for anything higher. No matter what the enclosure needs to be white or light grey.

I’m clearly missing something here. My experience with LNB’s for TVRO is that the drive from a LNB is substantial, currently I have a 40m co-ax between my satellite receiver and the LNB.

So rather than weatherproofing the unit mount it away from the LNB in a dry location ?

If my unit - which seems to be coming on a three legged donkey ever arrives I’ll comment further.

I think the idea @Syed is working on here is to be able to sell a unit that can all fit in a weather-resistant carry box and be easily put together in the field, such as in the parts of a country where there is no phone nor internet easily available.

Blockquote I’m clearly missing something here. My experience with LNB’s for TVRO is that the drive from a LNB is substantial, currently I have a 40m co-ax between my satellite receiver and the LNB.

So rather than weatherproofing the unit mount it away from the LNB in a dry location ? />

I believe what you have stated is a good case for experimenting, and a number of us have done just as you said, with good success. @kenbarbi and myself, @maxboysdad both have units mounted indoors, and are running a length of RG-6 Quad cable to the outdoor LNBF. Ken’s is 500 feet from the LNB. Mine is about 40 feet from the LNB. Both units work fine that way.

I’d say that 500ft is pushing it. After all we are talking about signals up to 1Ghz and RG6 is not ideal. In the UK WF100 is the most popular cable for sattv enthusiasts although the commercial installers like shotgun cable.

I’d have thought a two piece design would be best for alignment featuring a small dish. Squarials proved too expensive to make and currently LNB’s are dirt cheap and offer amazing performance over what we had 20 years ago. I’m on the edge of a footprint so every little helps and for tv have a 1.8m dish where alignment is critical and the signal level changes as the satellites move around in their box.

I’m using 500 ft of low loss RG-6 cable (the kind Comcast uses in buried installations) with my Maverick on an 80 cm offset FTA dish. Here’s my Tuner App data - -

Inside, at this time, I have a -94 dBm Rssi. At 1 GHz, standard RG-6 has about 6 dB loss per 100 feet. When I connect my Dreamcatcher outside, I get -74 dBm Rssi. An expected 20 dB drop - - usually my signal levels are more on the order of -102 dBm. All other signal parameters are the same - - especially the SNR. Ken

As there are no errors there is enough signal and signal quality. On my 40m run I experimented with a line powered amplifier half way and determined the results were better without it. This on TV as my dreamcatcher is ordered but not seen.

The LNB can be removed from the box, for use with a dish.

Do you you still test the Dreamcatcher v3.05s with a 50 foot cable run to the LNB before you send them out to customers? Ken

No, that’s not a use case we directly support. Since we do have a pass 14V over the cable, it should not be a problem.

What kind of test then do you perform? Ken

It’s a functional testing of Skylark, wifi, and reception from a live signal coming through a bare LNB over ten feet of RG-6 and three feet of RG-58.

Why the mis-matched impedances 72 ohm to 50 ohm coax?

It’s done on purpose to introduce additional loss in the RF chain.

Makes good sense to me. Just unusual. Is the DreamCatcher’s input actually a 72-ohm device?

I’m not sure I understand the question, but as more information:

The LNB is outputting 75-ohms–no way around that.
The Dreamcatcher is expecting 50-ohms, but the losses from the mismatch are not huge.
From the u.fl/IPEC connector backwards (on the board), everything is 50-ohms.

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I appreciate your time and explanation. The question arises from my having worked with transmitters a good deal of my professional life, and the importance of impedance matching. As we are working with just a receiver in this application, I understand the answer provided. Thanks!

The 3D print of the latest design just came.



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Here is what is not apparent from the pictures.

  • The LNB can be twisted/skew-adjusted and stay in place
  • Both of the holes next to the LNB are water tight
  • The LNB can be removed and the hole is closed with a plug
  • The F-connector allows for optional remote placement of the LNB
  • A cover will be placed on top of the Dreamcatcher
  • The bottom allows a stand to be attached for elevation adjustment
  • There may be foam on top of the Dreamcatcher to hold a battery in place
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