Help re: C band NOAAport LNB wiring

[racrman]

I could use some help with this one. I've assembled a 8' C band dish with a Chaparral LNB. I'm going to use this for a NOAAport receiver system. The Novra S75 receiver has no jack for the LNB 20 gauge wires, however.

Does this mean the LNB servo does not need power?

If it does need power, how does the power reach the LNB without the standard power jacks (3 wires)?

Is power supposed to reach the LNB through the coax?

Thanks.

Michael Allen,
Plymouth, MN

 

[photoman76]

If this is a fixed dish system and will be use for NOAAport only, then you probably don't need to connect the servo motor wires. The Novra S75 receiver will supply voltage to the lnb via the coax. You may need to rotate the feed horn to fix the desired polarity.

 

[chefwan]

what is NOAAport ? i've never heard of it ?

 

[bryansr]

what is NOAAport ? i've never heard of it ?

This is to receive the Weather information off the satellite directly from NOAA. It requires a computer driven satellite receiver. I hooked one up & peaked it a few years ago, for the state, and it was a ROYAL PAIN. It took 2 hours of VERY SLOWLY ADJUSTING, using the slightest adjustments, the dish to reach the PEAK Signal using a computer to get to the peak signal strength. I Lost the peak it and it took another 2 hours to get the signal peaked again. The engineer that was running the computer told me He got a better signal in Oklahoma City and SHOULD be able to get the same here. I told him NO WAY! We are located further away from the prime area of the "footprint" than OK City. I told him that if he wanted a higher signal he had to get a BIGGER DISH. He then tought a minute and said that must by why Miami had a LOT bigger dish when he went there to set up their system. He could run the computer BUT he could NOT peak the dish.
This was a contract job.

BryanSR

 

[racrman]

Thanks to all of you! To photoman: Because the receiver doesn't have a jack for the servo, I assumed it received power through the coax, but I needed to make sure. In the meantime, I reviewed the material on the polarity adjustments and the need to the proper turn in the feedhorn. It now makes much more sense. Simple geometry (or trigonometry).

To Chefwan: Yep, NOAAport is the NWS satellite feed for data. There just isn't any other source for the data. I would have lugged home a bigger dish, but I found two of these in SW Minnesota! I live in the Minneapolis, MN area and I thought I'd give this one a try. If I need something bigger, I guess I'll have to look harder for it!

I hope it's not as difficult to aim this thing as it sounds. I have fabricated a post and stand for it by welding up a dollied frame, and building it for stability and the ability to level it has been a challenge. I understand now why "size matters." I guess we'll see how this works.

In the meantime, at least I have the powering question done. Those of you with systems needing to turn and find multiple birds must have an interesting time of it...

Thanks again. Mike (racrman)

 

[adrian]

LNB wiring

As a matter of interest ,in the case of a moving system,using a receiver without a connecting jack for the servo motor wires,will the coax supply the power to move the skew.It follows that the three wires are not connected anywhere.

 

[chefwan]

cool

This is to receive the Weather information off the satellite directly from NOAA. It requires a computer driven satellite receiver. I hooked one up & peaked it a few years ago, for the state, and it was a ROYAL PAIN. It took 2 hours of VERY SLOWLY ADJUSTING, using the slightest adjustments, the dish to reach the PEAK Signal using a computer to get to the peak signal strength. I Lost the peak it and it took another 2 hours to get the signal peaked again. The engineer that was running the computer told me He got a better signal in Oklahoma City and SHOULD be able to get the same here. I told him NO WAY! We are located further away from the prime area of the "footprint" than OK City. I told him that if he wanted a higher signal he had to get a BIGGER DISH. He then tought a minute and said that must by why Miami had a LOT bigger dish when he went there to set up their system. He could run the computer BUT he could NOT peak the dish.
This was a contract job.

BryanSR

That's cool learn something new everyday. wish you luck racrman :up

 

[crankbooster]

I could use some help with this one. I've assembled a 8' C band dish with a Chaparral LNB. I'm going to use this for a NOAAport receiver system. The Novra S75 receiver has no jack for the LNB 20 gauge wires, however.

Does this mean the LNB servo does not need power?

If it does need power, how does the power reach the LNB without the standard power jacks (3 wires)?

Is power supposed to reach the LNB through the coax?

Thanks.

Michael Allen,
Plymouth, MN

Since the dish will be picking only from one satellite I will andvice you slave and analogue receiver to the dish and use it to peak the polarity and disconnect it after sucessfull installation.
I hope this does not sound stupid.

 

[racrman]

Crankbooster: That sounds like an excellent idea. There are two types of software to use, one from the Novra receiver folks with enough information to choke two horses. The other is from an academic site in Puerto Rico. The Puerto Rican software is extremely well done, collects and catalogs the data, and gives the user an opportunity to administer all the data entering the system.

That's a very important issue, in this case. Each day, NOAAport can dump 15 to 20 GB of numbers on the system's hard disks; that's a lot to manage without it piling up until you can't see out the windows! In addition, I also have a data feed from several federal agencies affiliated with the NWS, so lots of numbers can collect in lots of formats!

It's all a pain to manage, but the numerical models are hungry: like my dog, if the food's in the dish, he'll eat it, no matter what!

You guys should be glad you're using your systems for other things: all I get is a bunch of numbers!

racrman

 

[chefwan]

Crankbooster: That sounds like an excellent idea. There are two types of software to use, one from the Novra receiver folks with enough information to choke two horses. The other is from an academic site in Puerto Rico. The Puerto Rican software is extremely well done, collects and catalogs the data, and gives the user an opportunity to administer all the data entering the system.

That's a very important issue, in this case. Each day, NOAAport can dump 15 to 20 GB of numbers on the system's hard disks; that's a lot to manage without it piling up until you can't see out the windows! In addition, I also have a data feed from several federal agencies affiliated with the NWS, so lots of numbers can collect in lots of formats!

It's all a pain to manage, but the numerical models are hungry: like my dog, if the food's in the dish, he'll eat it, no matter what!

You guys should be glad you're using your systems for other things: all I get is a bunch of numbers!

racrman

What do You Do When You Get All That Data? Send it to other's? or what

 

[racrman]

Sorry this has taken so long to reply: I've been out in the yard configuring this thing! I got it from a place that used to provide commercial service. I found lots of mistakes in the configuration: the feedhord adjustment (the f/D ratio) was set wrong: it should have been 0.42; it was set at 0.36. The scalar rings were not parallel to the dish. And the focal distance was off by 6 INCHES!! I don't know how they got anything on it, except I suspect they moved the feedhorn in to adjust the focal distance.

Now, to answer your question: The data goes into numerical models for forecasting the weather. It's kinda' a long story, but the data is the raw material, the numerical models are mathematical means of modeling the atmosphere over North America, and the result is a series of forecasts for the middle section on the U.S. My clients are primarily in agriculture and I furnish them with any of about 50 parameters that they use for fertilizer application, seed patterns, plant disease forecasts, and various aspects of sun energy and the exchange of gases for plant transpiration. I also furnish others with information regarding auto racing (no, not the really big guys: I can only wish!) and finally, lots of construction companies in the metro area (Minneapolis/St. Paul).

In a nutshell, that's the story. The numbers are the initial key ingredient, since they describe the reality of the atmosphere at any particular time.

racrman

 

[chefwan]

Sorry this has taken so long to reply: I've been out in the yard configuring this thing! I got it from a place that used to provide commercial service. I found lots of mistakes in the configuration: the feedhord adjustment (the f/D ratio) was set wrong: it should have been 0.42; it was set at 0.36. The scalar rings were not parallel to the dish. And the focal distance was off by 6 INCHES!! I don't know how they got anything on it, except I suspect they moved the feedhorn in to adjust the focal distance.

Now, to answer your question: The data goes into numerical models for forecasting the weather. It's kinda' a long story, but the data is the raw material, the numerical models are mathematical means of modeling the atmosphere over North America, and the result is a series of forecasts for the middle section on the U.S. My clients are primarily in agriculture and I furnish them with any of about 50 parameters that they use for fertilizer application, seed patterns, plant disease forecasts, and various aspects of sun energy and the exchange of gases for plant transpiration. I also furnish others with information regarding auto racing (no, not the really big guys: I can only wish!) and finally, lots of construction companies in the metro area (Minneapolis/St. Paul).

In a nutshell, that's the story. The numbers are the initial key ingredient, since they describe the reality of the atmosphere at any particular time.

racrman

Sound's Cool. good luck

 

[adrian]

LNB wiring

Referring to my earlier post on this thread can someone please advise me
the position with regard to the servo motor wires ,where there is not a connecting facility on the newer receivers.Also if the servo motor is removed will any current in the coax turn the skew.

 

[dem0nlord]

No, there's no way to change skew via coax. You either need equipment that gives you skew control, or replace the feedhorn/LNB with an LNBF or orthomode feed/LNBs to voltage switch between polarities and that has no skew control.

 

[WyrTwister]

Referring to my earlier post on this thread can someone please advise me
the position with regard to the servo motor wires ,where there is not a connecting facility on the newer receivers.Also if the servo motor is removed will any current in the coax turn the skew.

Let me see if I understand this correctly . You will be looking at one sat , one transponder , one polarity ? On C band ?

Think you can physically rotate the feed horn to adjust for skew & then leave it there .

Wyr

 

[adrian]

LNB servo motor wires.

Thanks for the response.My dish is moving.Does it follow that there is no way that a LNBF with a servo motor can be used with a receiver,without a connecting port for the three wires.

 

[dem0nlord]

Thanks for the response.My dish is moving.Does it follow that there is no way that a LNBF with a servo motor can be used with a receiver,without a connecting port for the three wires.

An LNBF doesn't use a servo, a feedhorn with an LNB does. So either switch to an LNBF(or orthomode feed), or get a receiver that will control your polarizer.

 

[adrian]

LNB servo motor wires.

Sorry,i meant LNB.I am of the impression that you can not connect servo motor wires to the most recent receivers.Is there a way around this other than to purchase a LNBF.

 

[dem0nlord]

Is there a way around this other than to purchase a LNBF.

Yes, 2 other ways that have already been given to you.

1. Purchase an orthomode feedhorn and 2 LNBs.
2. Purchase a receiver that will control your polarizer.