Free Supplies for Cone Extension Experiment

Could you share drawings and more detailed pictures of the DIY wave guide?

Nice work, Ken!

DIY Wave Guide
Made out of aluminum flashing from Home Depot or Lowes. I taped the 4 trapizoid sides together with duct tape.

Several folks made it out of garden chicken wire which is more wind proof.

chicken

Ken

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How did you come up with those dimensions?

I took the martini shaker dimentions which I first tried and cut trapizoid paterns so I could piece it together in a foldable format for transport. I also looked at wave guide dimentions for 18 GHz sytems using wave guides which agreed with those dimensions and used them.

Not very scientific - - besides, I don’t drink martinis - - just wine :rofl:

Anyway, seriously, the specs of the martini shaker (2x4x8 inches) work well as Konrad’s antenna does and other’s are finding - -

Martini

@Konrad_Roeder will attest to that.

Ken

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@kenbarbi Your 4.5 dB improvement with the wave guide is much better than @Konrad_Roeder’s martini shaker. If you unmount the waveguide while connected to the LNB, how difficult is it to eyeball point?

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Knowing the general magnetic direction and elevation angle makes it easy to point by just looking for a spike in SNR from a -17 dB to a higher value around -14 dB. When I pass that point, I slow down my movement of the LNB to get a peak reading.

The one issue I have is that I mounted the touch screen on the front side of my portable terminal right under the LNB. Bad move, because to read the screen in sun light requires you to be head on to the screen which blocks the LNB with your head. Otherwise the glare prevents you from reading the SNRs.


(By the way in this picture I haven’t optimized pointing - - my elevation is too low and I am standing in front of the LNB to take the picture)

Ken

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I’m using a simple cone made from a paper cup and some aluminum foil and it works great.

Ken did you have to add a ribbon cable to the display?

Tyler, your paper cup assembly should work fine too as you’ve found out.

Yes I did add a short ribbon cable with a male connector at one end, and a female at the other. As you guessed, the display should have been mounted elsewhere on my travel case so I could read the display in bright sun. That’s usually the direction my LNB is pointing when I site it. Ken

I guess I have a questioning mind. There is no longer any discussion on signal strength, cone’s, antenna mounts.

Did the format/mode changes back in September really solve the snr issues ? Or was there an increase in satellite xmit power ? What do we need to expect if/when the next geographic area gets satellite coverage ? What parameters changed to allow the signals to be easier to receive / decode ?

The other question I have is - - what was the the effect of the recent MODEM replacement at the MD earth station have. SNR increased about 8 dB here (however Rssi remained the same).

Perhaps some of us who installed cones and wave guides should temporarily remove them and report results. Ken

@ac8dg We are currently designing a flat panel antenna that is a bit higher gain than the Maverick. Designing patch arrays is tricky business so it is taking some time and there is sometimes two steps forward and one step back. The problems at the teleport had nothing to do with SNR; it was a hardware issue.

We need to finalize the front end before we can expand to Europe and Africa. I’m hoping the antenna design will finish by the end of this month. A higher gain antenna does allow for better reception quality. Of course, higher gain also means smaller beam width, which makes it harder to point. It’s a bit of a trade.

@kenbarbi We ended up not needing to replace the modem. It was another hardware issue. I’m not sure how SNR increased by 8 dB for you. We saw maybe a 2dB improvement.

Thanks for the update, just for info,
I have a signal of +5 snr, yes that is right a positive value.

What is your antenna for +5? I have about the same gain using DirecTV dish and Maverick LNB.

Hmm @Syed are there any plans on like a golf ball attenna style so even if it high gain we could get higher data transfer then what it has now with a some what of a Omi directional attenna?

No plans on a golf ball antenna.

Trust me - - my Dreamcatcher 500 ft away from my Ku-band FTA offset dish/LNB did increase and is still running hi. I think other will confirm higher SNRs.

I took my portable terminal outside just now to compare with my observations. With a bare LNB, I immediately found the satellite by aiming ruffly at the sky receiving a signal with an SNR of -7.25dB and Rssi of -77 dBm. When I pulled up my expandable cup cone, my SNR jumped to -3.75 dB with an Rssi still at -77 dBm.

You’ve done something :rofl: Ken

PS

I think it will be worth your while finding out what else got tweaked. 8 dB is nothing to sneeze at. Ken

@donde my antenna is similar , the 18" dishtv but with a non-maverick lnbf, I found on ebay a linear v/h with a rectangular insert that fit the original boom mount. The ‘stock’ dishtv lnbf was circular and the wrong frequency range.