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Ku-Band Installation FAQ

The following are answers to some of the most frequently asked installation questions about Ku-Band service.

I can’t find the satellite. What am I doing wrong?
The most common mistake is not ensuring that the antenna mast tube is plumb. If the tube is not plumb, the built-in inclinometer scale will not be accurate and a lot of time may be wasted looking in all the wrong places.

How accurately do I need to point the antenna just to get a lock light?
The beam width for these antennas are considerable narrower than those for the smaller C-band Weather Wire antennas that many of you are familiar with. On a clear day, you can expect a lock light when the antenna is within the 10dB beam width. On a cloudy or heavy overcast day, the signal can be attenuated an additional 3 to 7dB. Cloudy/overcast days require greater initial pointing accuracy (i.e. 3dB angle) to get a lock light.

Do I need a spectrum analyzer to correctly install a NOAAPort Lite system?
Although a spectrum analyzer is useful in identifying the NOAAPort Carrier at its down-converted L-Band frequency of 1.0709 GHz, it’s not absolutely necessary.

OK, I borrowed a spectrum analyzer. What does the signal look like?
Earlier this year, we plotted the signal with the display parameters as shown in Figure 1. The NOAAPort Lite signal is the large lump in the middle. The signals on either side of NOAAPort Lite are not under our control. Therefore, they may have moved up or down, to or fro. Because NOAAPort Lite is operating at the maximum FCC allowable transmit power, it is unlikely that other signals will be at a substantially higher level. If they are, something is amuck. Repeat the antenna/LNB combination.

I don’t have access to a spectrum analyzer, what about others signal measuring hardware?
Channel Master and others make non-selective, broadband signal meters that are useful for finding the satellite location.

You say "finding the satellite location" not finding the NOAAPort Lite carrier. What’s the difference?
The NOAAPort Lite satellite (currently GE Spacenet IV) is located at 101^o W longitude. Also located at 101^o (actually at 101.2^o and 100.8^o) are three Direct TV Direct Broadcast Satellites (DBS). DBS satellites are part of the Broadcast Satellite Service (BSS) and transmit a circularly polarized signal 500MHz higher and 10dB hotter than the linearly polarized Fixed Satellite Service satellite (i.e. Spacenet IV). Although linearly polarized and designed for the BSS, the NOAAPort Lite antenna/LNB will receive and downconvert DBS signals. The broadband detectors (see previous answer) will demodulate these signals and help peak the antenna to 101^o W.

So what’s the problem?
The antenna/LNB still needs to be peaked to the NOAAPort Lite carrier.

And how do I do that?
A relative indication of signal strength is available by measuring the DC voltage on pins 1 and 10 of the 15 pin D synchronous high speed data connector labeled "PORT 1". A higher level of this AGC voltage represents a greater signal strength. Adjust the azimuth, elevation, and polarization for maximum voltage.

The AGC voltage appears to jump for no apparent reason. Is this normal?
Yes, the receiver is switching digital filters and internal gain setting to optimize its performance. This commotion should stop after 5-7 seconds.

With Spacenet IV and the Direct TV satellites at the same location, can I use the neat CSC alignment program to verify azimuth and elevation values?
Roger that. The Digital Satellite System jointly used by Direct TV and United States Satellite Broadcasting (USSB) has a nifty alignment program which converts zip codes into azimuth and elevator settings.

How about the Echostar, Alphastar, DISH Network, or Primstar programs? Will they work?
No, only the CSC (a.k.a. Direct TV or USSB).

What’s the polarity of the NOAAPort Lite carrier?
NOAAPort Lite is horizontally polarized which means the long dimension of the waveguide flange is up and down. The single polarity feeds are factory assembled for vertical polarization. Be sure to rotate this field 90^o (clockwise or counter-clockwise) before starting this peaking process.

There’s a Weather Wire 30" antenna next to the NOAAPort Lite antenna. Aren’t they both pointing to the same bird?
That’s right. The Weather Wire antenna also points to Spacenet IV. You can get a rough idea of the azimuth heading by looking at the Weather Wire antenna. Be forewarned that the Weather Wire is a center feed antenna and NOAAPort Lite is an offset feed. Subtract 22.6^o from the Weather Wire antenna elevation to approximate the NOAAPort Lite elevation. Better yet, accurately plumb the mast tube and set the inclinometer to the correct elevation value.

How much ballast do I need?
Tables are included in the 1.2 meter manual for ballast deployment. The 1.2 meter base frame is designed to hold 8" x 16" x 4" concrete cap blocks (patio block) weighing about 32 lbs each. The 1.8 meter roof mount is designed for 39 lbs, hollow core concrete (a.k.a. cinder) blocks. The proper number of blocks for the 1.8 meter is detailed in Table 1. For the 2.4 meter, proper placement is a little trickier. Call our ballast man, Larry Brooks at (703) 818-4694. He will take down all required site location information and get back with the proper ballast requirements.

Table 1.    Number of 39-lb. Concrete Blocks Required

 

NR = Not recommended

To achieve a static friction coefficient of 0.75 on a built-up roof (tar & gravel), a 1/8" thick rubber matting must be placed between the ballast trays and the roof. Any loose gravel should be removed from the area under the rubber matting.

Exposure Level "B" Urban, suburban and wooded areas with numerous, closely spaced obstructions the size of single family houses or larger.

Exposure Level "C" Open terrain with only scattered obstructions, generally less than 30 feet in height. This includes flat, open country and grasslands.

The LOCK light is doing funny things. What’s going on?
The LOCK light is a bi-colored light emitting diode. It can indicate a number of system conditions.

Solid Green Indicates that the demodulator is locked onto the satellite carrier.

Green With Off Pulse Indicates the demodulator has locked to the carrier but no Station Identification (SID) has been found.

So where do we find SID?
Initially, all receivers were (supposedly) programmed with all receive characteristics, including SID, at the factory or at our Chantilly, VA location. If you’re reading these instructions after July 1998, we are able to remotely download receiver configuration changes using the satellite transmission system. Call the NMOC Help Desk at 1-800-635-4679 and request verification of the receiver’s programming. If it’s not July 1998 yet, the receiver must be replaced with a properly programmed unit. Call the above number and complain.

What else can the LOCK light indicate?
In addition, the LOCK light can indicate:

Solid Green The demodulator has not locked onto the satellite carrier.

Off, Green/Red Flicker Indicates the demodulator is attempting to lock but the signal has degraded.

The LED will flicker from green to red as the performance degrades giving a rough indication of Bit Error Rate (BER) or Carrier to Noise (C/No) ratio.

These conditions most likely indicate faulty equipment or improper antenna/LNB positioning.

I’ve finished the installation and everything is working well but the customer thinks the ground mounted antenna is an eyesore. Is there anything he can do?
Ask the customer to check with the NOAAPort Lite Program Manager, Gerard Tribie, (703) 818-4940, concerning the status of plastic rock antenna covers. Available in 5 designer colors, the manufacturer’s existing line of plastic rocks are too small to cover even the 1.2 meter antenna. If enough public interest is shown, the manufacturer may commission a custom rock for the NOAAPort Lite 1.2 meter and/or 1.8 meter antennas.

The customer thinks one big plastic rock next to his building/home looks stupid. What can I tell him?
The plastic rock manufacturer recommends additional baby rocks alongside the big rock to make the setting more natural looking. He is also developing a fake garden shed to shield the antenna. Contact the NOAAPort Lite PM for the details.

 

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