How A Simple Fix Makes A Big Difference


#1

Ok, so the $48 kit had been staring at me for a couple of weeks as I walked by the shelf. I pulled it out yesterday, and lashed the LNB up to a little pipe on the patio. It was only giving me -14.5 dB here in Colorado. That gave me a valid packet percentage of ~30% (clearly inadequate). It started to rain, so I figured I’d get to it tomorrow. This morning, I was browsing around in the pantry looking for a quick and easy fix. I pulled down a clear plastic single use cup, slit it down the side, and trimmed up the bottom to fit. It wasn’t perfectly aligned when placed on the LNB. After mounting it, I just squished aluminum foil around the outside of it, and ran the board. It was sloppy, but good enough to give me another couple of dB. With -12.5 dB my valid packet percentage went to 100%. It’s ugly, but an example of how a cheap, and ugly fix, can make a huge difference. Now give it a little time to load data, and I imagine I’ll be even more impressed. These were a good deal at the original price. It’s even better now. Certainly a great proof of concept. Regards!


#2

Try a Pringle jar - - they are aluminum coated on the inside.

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It was my venture into cones and wave guides and worked well giving me about 3 dB of SNR improvement. I enjoyed eating the chips too. Ken


#3

You are absolutely correct… for 10 cents of aluminum foil and a cup you can make that -14.5 dB marginal reception into a -12 dB SNR and good working setup.


#4

I wanted to use a Pringles can. I really did. However, “She Who Is To Be Obeyed”, has stripped the house of this valuable asset. More’s the pity, but $0.03’s worth of parts works wonders. I’m waiting for the aesthetic “review” to determine whether I can keep my creation out in the yard. :slight_smile:


#5

They have other flavors :yum: :yum:

Oh - - good luck keeping it in the yard!

Ken


#6

Get a small dish.


#7

I previously tried something similar: a 300ml plastic water bottle trimmed to fit around the LNB, then wrapped on the cylindrical sides with aluminum foil. But it made no improvement. I had thought the metallized tube would improve SNR by keeping some noise away from the LNB. But maybe a conical structure works better to reflect more signal into the LNB? Later when I have time I will try your scheme with a conical cup. Thanks for the tip. I’ve been getting about -13.5 +/-1 dB with a bare LNB, near Vancouver BC Canada.

I’m not sure I am using proper RG6 coax cable; I grabbed something from my junk cable drawer and it worked enough. But a different cable certainly did not work. Over the past month of tinkering with satellite receivers, I have learned that it is important to understand what you’re doing, and start with known-good recipes. There are more ways for these setups to not work than work.


#8

I covered a conical plastic beer cup (bottom cut off) with aluminum foil, then taped it to my Maverick MK1 LNB, then took my Dreamcatcher 3.03 to a park where I have line-of-sight to the SES-2 satellite. Pointing and signal acquisition was fairly easy, SNR bouncing around -12dB, with 100% packet reception.

Then I ripped off the beer cup, and subsequently had a very hard time re-acquiring the signal, and never got better than -13dB SNR, usually worse, and never 100% packet reception. So even a simple messy foil cone added about 2dB SNR improvement which provided great benefit in a marginal signal zone.

I put the damaged cone back onto the LNB, and again got a worthwhile improvement.

Next time, I might leave my laptop at home, and just bring earbuds to listen to VOA audio.