SatSig topic:

WB meters

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Jul 18^th, 2009 at 5:38am

glad I found this site...it didnt show up on google much for some reason...
anyway..I saw a post in this forum and the mod. said that even cheap meters
would work with WB if you had a filter. I un derstood that you only need the apa on the initial install..comments? Why would a cheap analog meter work in the ka band..?? dont they need the extra freq. circuits in them..??
I ordered the standard cheap,20$ meter that most people use and its mostly for Dish TV.. will that thing really work for WB..??
I was losing connections recently after I bumped my WB dish....so I peaked it by hand. I didnt know it would work but it did.I just loosened the 4 bolts under the AZ and tried several settings close to the mark that I had made on the metal awhile back and finally I got a connection and its a good one.I didnt even do the elevation at all,and I bet it would be even better but I'll wait for a meter.You can tell if its got a satellite when the modem blinks both lights2 and 3 before the solid 1 and 2 lights. Strong enough I guess at 70K download and no disconnects. I used to average 60K.Value package.
What do you think of that..?? And any specific info on a meter appreciated??
I thought you had to buy the 500$ meters for WB,,,no wayyyyyyyyyy..

Jul 18^th, 2009 at 9:26am

A cheap satellite meter is a wide band power meter, like an untuned crystal set, that 'listens' over the range approx 950 - 2150 MHz, called L band, which is the range of frequencies in the LNB cable.

When the antenna is pointed at cold sky the signal being measured is the noise power from the front end transistor in the LNB. This noise floor signal will cause the needle to hardly move off the zero scale position.

Once pointed at a satellite the meter starts measuring the power of the visible satellite carriers in addition to the noise floor. A typical TV broadcast satellite will have many carriers, occupying a large proportion of the 950 - 2150 MHz bandwidth. The result is that the meter reading goes up substantially, which is what is wanted.

In the case of a satellite with perhaps only one carrier visible then the reading on the meter will be very small. This will not make it impossible to use the meter to peak up but you will need to be alert to even a tiny movement of the needle. A magnifing glass might help you detect the needle movement and the peak.

The WildBlue satellite has multiple spot beams and if you are in the centre of a beam then you will see only one downlink carrier. If you are at a beam edge you might see two or three downlink beams. Obviously 1, 2 or 3 carriers is far fewer then the total of 45 carriers so the reading on your meter will be far lower than for a TV broadcast type satellite which has one large beam and multiple carriers visible to everyone simultaneously.

The expensive meter has a filter so it listens just to the wanted carrier frequency in your beam. When off satellite it detects only the noise floor corresponding to the wanted carrier frequency. When on satellite it detects the wanted carrier. The result is a large change in the measured power between off satellite and on satellite. More amplification to the needle is needed since only one carrier is being detected, but the important thing is the big improvement in carrier to noise ratio which make is much easier to peak up - so no magnifing glass needed to see the needle move !

I don't recommend using the LEDs to peak up with WB since, during mispointing, the system will be dynamically adjusting the downlink and uplink bit rates, power levels and FEC code rates in an attempt to keep your terminal working under the false impression that you have an erratic and heavy rain storm in progress.

Best regards, Eric.

Jul 18^th, 2009 at 1:17pm

The APA (filter) is technically only needed for the initial setup and/or when relocating the dish. It's used in conjunction with a signal strength meter. Once the correct signal is acquired and the modem becomes "commissioned", any simple $10 analog "satellite signal finder" is all that's necessary to periodically peak the Wildblue dish. Take care though, not to lose the signal altogether, as it may become necessary to involve an APA to properly recover.

Take care also that you connect the meter to the correct cable. As Eric stated, the RX cable carries a L-band signal. The Wildblue TX cable on the other hand, carries a S-band signal. You'll get nowhere fast putting the meter on the wrong cable.

//greg//

Jul 18^th, 2009 at 4:03pm

thanks for the detailed info... when I was tweaking by hand, I did move the
dish enough to lose the beam? totally..I only had 1 light on the modem blinking..
the 3rd light was off... but I got the signal back by moving the dish...I had planned on moving the dish
in a couple of months ...do you think that will be a problem? is it because I will have to disconnect the 2 cables from the tria..?? I thought I could get all the
general sets correct and level and just tweak again by hand...what do you think of this...?? And what meters are good for WB? The super buddy is out of the question but are there others cheaper, could a radio hack make a modified
unit that would work, like something that Radio Labs might do.??Do you have to have the APA or is it built in to these better meters?I would spend 150$ on a meter but not more...1 service call pays for half of it...
it sounds like using a regular meter for WB isnt a good way anyway....
I had thought of going Hughes net internet..my contract is up next fall..
is it easier to peek their system.? I have heard they are a little faster for the money than WB. I really want to get proficient on peeking any kind of dish..
Is there an online GOOD signal meter and Sat info site OTHER than WB?

Jul 18^th, 2009 at 5:04pm

The cheapest meter will give an indication but you may need to look hard at the needle to detect it. It is perfectly adequate if you are patient and look very carefully. A second person looking at the needle with a magnifing glass might help while you move the dish. The first tiny movement will show you are getting near the satellite, then peak up. Peaked up, the needle movement will be small but quite clear.

The problem once you lose the satellite is finding it again. Fortunately there are only a few Ka band satellites around so if you get an indication it is probably the right one. Once you are peaked up your modem will eventually find the carrier. The modem has a complex process for looking for a carrier, searching various frequencies etc and may take some time to lock up, so it is not so practical to point the dish around hoping to find the satellite using the LEDs. This will particularly be true if you move it to another beam coverage area. Tell WB what you are doing and the new site lat/long location.

Lable the four ends of the cables very clearly and turn the AC mains power OFF at the wall switch before disconnecting any cable. Move the dish and try with a cheap satellite meter. Good luck.

This satsig.net web site provides help on all types of satellite dish pointing problems, regardless of technology.

Best regards, Eric.

Jul 18^th, 2009 at 6:15pm

The situation you're in is that you're pointing at a pair of adjacent Ka-satellites, They're both at a nominal 111.1W, but are within ~0.25 degrees of each other. They both use the same RX frequency range (19.7-20.2GHz) , but opposite polarization. Anik-F2 is RHCP, WildBlue1 is LHCP. That's why it's kinda important - while in the process of peaking up - not to "fall off" the satellite to which you're assigned. You might get lucky and find it again by accident, or you might have to make that $125 phone call to get an installer to come out.

//greg//

Jul 18^th, 2009 at 6:43pm

but the bottom line is if your on the correct sat you will end up with a connection,
steady 1 and 2 lights. It might take awhile but....I am only moving mine 30 ft . What would help is a website
that would ID the sat I am hitting when I am doing this.It would show all the info on what signal you were getting.....And since my setup is already installed, my gear will select the correct beam 13..? is this correct?
Anik F2 beam 13 Left
I dont personally have to worry about the gear selecting the correct beam 13..
it will do that..??

Jul 18^th, 2009 at 7:24pm

Greg

I think the feed system on his TRIA is one specific polarisation so he should detect only his wanted satellite. I don't know if the polariser can be changed (e.g. by unscrewing and remounting 90 deg different) or if there are two hardware varieties of TRIA feed polariser to suit the two different satellites.

I am not aware of any 'web site screen' in the modem itself that enables the customer to see the signal quality being received and to help the customer peak up ? This seems to be a major deficiency of the DOCSIS modem.

This page (on this website) gives satellite dish pointing angles for the USA but this data is already known and moving the dish to the other side of the house will simply require a bold swing sideways followed by peaking up.

Best regards, Eric.

Jul 18^th, 2009 at 9:07pm

Ok, I think I can see that. The receiver itself is simply looking for above threshold signals between 19.7 and 20.2 GHz. Since the cast polarizer is actually in FRONT of the receiver, I can see where it acts as a "pre-filter" that reject signals of the opposing polarization.

The cast polarizer can in fact be rotated for either RHCP or LHCP operation.

You are correct that there is no Wildblue web interface, hence the need to employ a device on the IFL. A major deficiency indeed.

The cheap meters to which I referred have a gain control. As the signal strength increases, you reduce the gain. That preclude the need for extraordinary vision, you simple keep turning down the gain as the needle gets higher on the scale. When the needle peaks at minimum gain, you're done.

//greg//

Jul 19^th, 2009 at 1:39am

I appreciate the information.. other SAT websites are almost dead and you cant get any info from them..