1.2M offset Flat Vs Stacked Cone Scalar

[1ADAM12]

I replaced the lower lnbf arm with a 1/2" EMT conduit about 26" long and mounted the WSI LNBF holder on it. Set the front of the LNBF 30 7/8" from center of dish. and clamped the side arms with a hose clamp to make adjustment easy.

In my situation the Stacked cone Scalar outperforms anything else so far. I didn't go much further with peaking the dish because the first thing I tuned was NASCAR.

With the DMX741 with 1/2" spacer C and Ku have same focal point.

 

[Panavision]

What are the dimensions for the Walrus scalar? I followed the link of a previous post to another forum where he discusses his second best plans. Are these the plans you followed in constructing your scalar:

Small- 90mm inside circle diameter, 140mm outside
Medium- 90mm inside circle diameter, 200mm outside
Large- 90mm inside circle diameter, 260mm outside

Thanks for experimenting with this!

 

[1ADAM12]

Yes those are the numbers. I also made a cylinder 65 mm ID by 25 mm long that slides over the LNBF and the cones are glued to it. This allows the Scalarr to be adjusted. I also added a fourth larger cone and got improvement.

 

[Panavision]

Fourth cone, eh? After an evening of trying 3 cones with lackluster results, I will try another cone!

 

[Cadsulfide]

Nice work!

 

[Babadem]

Congratulations on your setup!!

 

[1ADAM12]

If you can't find tuning point with three cone Scakar, then you'll not have improvement with four.

Can you post pics of your Scalar and dish?

Some have not had improvement with DMX741 spacer either.

These results are good for dish and LNBF listed. Results will xery with location and experence.

 

[Panavision]

I'll have to take some pics tomorrow (at work right now). I am using the BSC-621-2. I've offset the C-band LNBF slightly left of center (Ku has that spot). I got the signal level up 3 percentage points by placing the C-band LNBF at center. You're right about the fourth cone; it did nothing.

 

[1ADAM12]

Did you skew the bsc621-2 to 9 O'clock?

 

[Panavision]

Yep, the LNBF is skewed correctly. I have included some pictures.

 

[1ADAM12]

Yep, the LNBF is skewed correctly. I have included some pictures.

Good pictures. Stacked cone Scalar looks good. Pictures can be deceiving but i'd say the BSC621 is aimed high on the dish. Looks like you have good toe in and side mount of LNBF should work good.

Don't give up on it it should be rewarding. When you get it tuned up, consider adding the 1/2" spacer to the Ku section.

 

[Panavision]

Thanks! I will definately keep working on it. After all, when is a setup truly finished? I would really like to use the BSC for Ku. I'll go through past posts about that spacer and try that. Centering the BSC did make a difference in % points by about 3. I can place a shim under the back of the BSC bracket to lower its "view" of the dish. I still have to align the Ku LNB portion of the BSC so its skew matches the C-band probes. I've done that before and it takes forever to get it tight and correctly aligned.

 

[Panavision]

From looking at others' pictures of the scalar, I wonder if I need to move it closer to the dish as seen in the photo. I'll have to create a new smallest cone so that it has a lip.

 

[1ADAM12]

Your scalar looks good to me the way it is. On the flat scalar the 1/8" setback is critical on my 90cm the setback is 3/8"

Use the same aluminum and cut a 1/2" wide strip about 11" long tape one end to the Ku scalar and wind it around to make the spacer. Tape or super glue the outside end of strip. Go to ACE Hardware and get a metric M3 about 15mm long they have both metal and plastic spacers too. I didn't put any silicon and don't get any water.

On my dish the lnbf is about 1" further away then the spec for the dish. 29" vs 30 7/8"

I put my Invacom on the shelf cause the DMX741 works so well.

Keep me posted

 

[Panavision]

Thanks for the instructions with photo! I would never have pictured what this looks like. I really want to get a DMX741u because of the lower noise temp and higher gain figure. I just bought a Geosatpro DSR200c. This will be my first time with blind scan.

 

[1ADAM12]

I added another pic that shows another approack to making to Stacked Cone Scalar as an assembly that can slide on the lnbf.

You got the whole weekend....have fun.

 

[srinath]

Your scalar looks good to me the way it is. On the flat scalar the 1/8" setback is critical on my 90cm the setback is 3/8"

Use the same aluminum and cut a 1/2" wide strip about 11" long tape one end to the Ku scalar and wind it around to make the spacer. Tape or super glue the outside end of strip. Go to ACE Hardware and get a metric M3 about 15mm long they have both metal and plastic spacers too. I didn't put any silicon and don't get any water.

On my dish the lnbf is about 1" further away then the spec for the dish. 29" vs 30 7/8"

I put my Invacom on the shelf cause the DMX741 works so well.

Keep me posted

Can you enlighten me on how did you put the whole thing together ?
How did you "glue" the pieces ? And how did you fix the ring on the LNB ?

I got my minibud setup here up and running with some interesting results and I would like to see if this homemade ring can help me get some extra Q points.

thanks

 

[kodaz]

in some of the other threads and perusing the net, it does suggest diminishing returns on a 4th ring, but , when i had my mini setup, i added a 4th ring the the store bought conical and got improved Q . changed my LNB to dish distance a bit though to dial it in (FD)
I have no idea where, but i think i posted it on this site somewhere. if not, here is another.

I did move on to a bud!

Kodaz

 

[Panavision]

I just got my DMX-241 and the homemade aluminum scalar ring really has a positive effect on my quality. I'm picking up stuff the BSC-621 couldn't get. The scalar didn't have any effect on my old BSC-621. Weird! Next I'll place the separate rings on a core to keep them from shifting in wind and snow.

 

[1ADAM12]

Scalar Pics.

I just got my DMX-241 and the homemade aluminum scalar ring really has a positive effect on my quality. I'm picking up stuff the BSC-621 couldn't get. The scalar didn't have any effect on my old BSC-621. Weird! Next I'll place the separate rings on a core to keep them from shifting in wind and snow.

Can you post a photo when finished?