AMC16 Linear or Circular?

[Clancy]

I know it has been established here that AMC16 at 118.75 is operating in the FSS band with a circular polarity.

I am wondering if at the moment it is transmitting both linear and circular signals.

What makes me wonder is the following quote from a DBS Talk poster.

With my 30" dish with linear LNB, I 'm getting a channel "TV 9903" off transponders 11.840V and 11.839H. It shows "Congratulations! You have a DISH PLus." with music.
Is it from 119 or from 118.7?

[Also, I tried to connect my 301 receiver to this cable, and it does not show anything, only coolsat does] end of quote.

Anyone here that can talk with an insider at Dishnetwork?

 

[Mr Tony]

Clancy
it does work with a linear LNB but it is very low signal. I was able to get the "you have a DishPLus" with a linear LNB...although at a 20 quality (30 is normally standard to be stable picture on a FTA box)

It is possible to use the wrong tyope of LNB in some cases, but the signal is low or non-existant

 

[SatAdam]

I got it with a linear with about a 40 signal this morning, couldn't hit it again to save my life.

Circular doesn't get it at all. (I did not move the dish, using invacom quad.)

That "You have a Dish Plus" page was pretty. Now I'm done with that. Time for another toy I think I am going to wonder to the PC card forum.......

 

[photoman76]

I got it with a linear with about a 40 signal this morning, couldn't hit it again to save my life.

Circular doesn't get it at all. (I did not move the dish, using invacom quad.)

That "You have a Dish Plus" page was pretty. Now I'm done with that. Time for another toy I think I am going to wonder to the PC card forum.......

I'm not surprised that you can't get it with the invacom quad circular. The frequency 11840R is way lower than the specs for the invacom lnbf. I can't tune it with my circular dbs lnbf. But I can see it with a linear lnbf. It all depends on how strong the signal is in your area and how well your linear lnbf rejects adjacent signals.

 

[Clancy]

Clancy
it does work with a linear LNB but it is very low signal. I was able to get the "you have a DishPLus" with a linear LNB...although at a 20 quality (30 is normally standard to be stable picture on a FTA box)

It is possible to use the wrong tyope of LNB in some cases, but the signal is low or non-existant

Thanks for the reply.
I have a couple of old Star Choice LNBF's operating on the required FSS band, their frequency drift is pretty good so when I get time I might hook them up to some spare dishes. I will be able to test as high as a 10'.

 

[Smith P.]

Look again at pertinent info:
range 11.7...12.2 GHz
polarty: circular
LOF 10.75 GHz (for Dish receivers)

Here some pictures http://dbstalk.com/showpost.php?p=589831&postcount=72
and discussions http://dbstalk.com/showthread.php?t=58318

 

[larrystotler]

Correct - A DBS LNB will not pick up those signals(maybe the highest ones). Further, AFAIK, you can't transmit both H/V and circular at the same time. It doesn't work that way.

 

[Smith P.]

Please read notes to that pictures - DBS LNBF will pick up those transponder ( actually did and do ), a problem is the IF : 450...950 MHz - out of input range of all receivers and cards.

 

[photoman76]

Please read notes to that pictures - DBS LNBF will pick up those transponder ( actually did and do ), a problem is the IF : 450...950 MHz - out of input range of all receivers and cards.

Ok, I now understand what you are saying. The problem isn't my circular lnbf, but the fact that my Broadlogic card will only tune down to IF 775MHz. That's why I'm seeing the higher frequencies, but not the lower ones.

 

[Smith P.]

right, if you'll find a way to decrease LOF in your LNBF to 10.75 GHz, then all transponders will be seen

 

[photoman76]

right, if you'll find a way to decrease LOF in your LNBF to 10.75 GHz, then all transponders will be seen

Another option is to attach a dielectric plate at 45 degree angle on the end of the linear lnbf. For the dielectric plate, I cut a small piece from a poly cutting board and taped it to the end of the linear lnbf. It cleaned up the Broadlogic Spectrum analyzer plot quite nicely.

 

[Smith P.]

I see you're using universal LNBF now.
Yes, that's well known method converting linear to circular LNBF. Unfortunately it can't be used for regular Dish receivers due to lower LOF.

Your snapshots looks familiar for me - are you that guy who make the Broadlogic board working as SA ?

 

[photoman76]

I see you're using universal LNBF now.
Yes, that's well known method converting linear to circular LNBF. Unfortunately it can't be used for regular Dish receivers due to lower LOF.

Your snapshots looks familiar for me - are you that guy who make the Broadlogic board working as SA ?

Yes, I posted some over in FTA section.

 

[DK_Sat]

Photoman,

Can you post a photo image off the LNBF with the dielectric plate

Thanks,

 

[photoman76]

Photoman,

Can you post a photo image off the LNBF with the dielectric plate

Thanks,

I already removed it from the lnbf mounted on my dish. But here are a couple of shots showing what it looks like on a spare lnbf that I have.

 

[Smith P.]

thanks for the hint photoman76
there is my report with modded KuFSS LNBF http://dbstalk.com/showpost.php?p=593729&postcount=106

 

[DK_Sat]

Photoman,

Thanks for the photos.