[FONT="][U][B]Radar:[/B][/U][/FONT][FONT="] Thanks ever so much for the info; this has been a steep learning curve over the past week or so. At this point, I do not understand what SID, VPID and APID is or ”SR 3978KS/s” for that matter. Can you fill me in? I could not find transponder "TP 11991HMz". In fact, I did not realize my motor was USALS compliant—duh! So far, I have been using the disceqc 1.2 protocol and searching for birds in increments due to the online reports that USALS may not be completely reliable. I also do not understand why some transponders fail during scanning and why some show limited signal while others are very strong when they are from the same bird—is this due to differences in power output between transponders or polarization variances? I cannot imagine there are differences in azimuth!! Sorry if this seems so elementary. [/FONT]
[FONT="]South: 123W is at 180.1 degrees true South from me, so it is a natural choice for a reference bird. My plan now is to let USALS determine where the 123W bird "should be" and slightly rotate the motor on the mast until it is at max signal. I’ll then re-sweep the arc looking for birds to the farthest East and West of my location via the USALS protocol. Hopefully, the latitude and dish elevation adjustments will still be in sync for usable signals across the arc. I think I fully understand the method of tuning in the arc via adjusting the latitude (height) and dish elevation, so hopefully that will not be a major issue. I tried letting USALS find 123W; it’s close but is a few degrees off from my compass/string method.[/FONT]
[FONT="]Turbosat: My issue with ID is that the birds are not ID’d, and I am finding channels not listed in “The List”. I have no idea what sat they are coming from. The channels are ID’d just fine. I can email what channels I am getting if need be.
[/FONT]
[FONT="][U][B]Cyberham: [/B][/U]Looking at 15W, you must be on the East Coast. Can’t ”see” that one from here! 73.[/FONT]
[FONT="]
Anyway; tomorrow, (Tuesday) is the day to re-aim the dish using the USALS protocol. I'll report back ASAP.[/FONT]
[FONT="] [/FONT]
[FONT="]Thanks! 998ccc[/FONT]
998ccc,
Before you get too involved with your alignment and arc calibration, I want to ensure that you did not misunderstand the procedure I mentioned previously. I need to ensure that I clarify this because you stated it back to me incorrectly in your reply.
Getting the mast perfectly vertical is the first step. Setting the MOTOR latitude is then the next step. With the motor on the mast and the motor axis centered at the ZERO degree or reference position is where you want to ensure that the MOTOR latitude is precisely determined and set. After this point, you do NOT ever adjust the MOTOR latitude again. I will explain how to ensure that your MOTOR latitude is precisely set in just a little bit, along with some of the other things you asked about.
During calibration of the "arc", when you go off to one side of the arc you tweak the DISH ELEVATION, when you go back to the other side of the arc, you tweak the AZIMUTH ANGLE of the whole dish and motor assembly. DO NOT readjust the MOTOR LATITUDE. That should have been precisely set early in the game.
To set the MOTOR LATITUDE angle most precisely, you need to know your site or location's EXACT latitude coordinate. You state that it is ABOUT 38.6°N. Just being close will not cut it. You must be sure of the PRECISE latitude coordinate of your location. You can find this out through Google Earth really easily. You then set the motor to the same latitude.
You can read this latitude setting off the motor's mounting bracket (note that many motor's have two scales, one reads elevation and one reads latitude - so don't confuse the two). The motor's latitude scale is normally not marked off in very refined or detailed increments. The divisions may be 1°, 2° or maybe even 5° or none at all.
You won't be able to discern very accurately what 38.6° is on such a scale. You need an inclinometer, which is like a level, but it has a circular scale that reads out in tenths of degrees and has a weighted pointer that indicates the angle on the scale. The inclinometer has a flat edge just like a level. Place this flat edge against the TRUE flat portion of the bottom of the motor and read the angle shown. This will actually be the ELEVATION of the motor (to find the LATITUDE, you have to subtract the ELEVATION from 90°). Using this inclinometer, you can set your MOTOR LATITUDE much more precisely than just using the motor's stamped scale. Once the latitude is set, don't ever move it again.
Remember that the motor must be at its center of travel (indicated on the scale on the motor's underbelly... The motor TUBE usually has a pointer to indicate this). If the motor is not indicating zero degrees on its scale, use your receiver to command it to either GOTO ZERO or GOTO REFERENCE, maybe even a GOTO HOME function (this depends upon the receiver). That should ensure that the motor is centered. This is where you check the motor latitude angle to ensure it is precise.
Don't worry about the SID, APID, VPID right now.
You need to understand at least the SR (Symbol Rate), Polarity and TP (transponder) frequency. As you make your way across the horizon to check signals from various satellites, you have to utilize a specific transponder (TP) on each satellite and use that same TP everytime you go to that particular satellite. Different TPs on the same sat may read vastly different, so you don't want to check your arc calibration with a totally different TP or you may and probably will get confusing data. In other words, compare the apple to the apple.
SR or Symbol rate is just the transmission rate (how many packets of data are being sent per second). You don't need to understand this in detail right now, but you need to ensure that it is set correctly if you have to enter it yourself. In many cases, you have to tell your receiver what the transponder frequency is and what its SR is so that the receiver knows what signal to look for coming in from the antenna.
For example, let's say you were in the process of calibrating your arc and you happened to be at satellite AMC21 @125.0°W. A good transponder to check here would be 12112 MHz, Vertical Polarity, SR 8702KS/s. Everytime you come back to check the signal and quality level on this satellite, use this same TP. Or maybe you are at satllite Galaxy 18 @ 123.0°W. A good TP might be 11776 MHz, Vertical polarity, SR 2848KS/s. Everytime you come back to the this sat to test your calibration results, use this same TP. Always use the same TP when you return to that specific sat to judge your calibration progress.
You will want to use "The List" or ask what a good TP to use for testing on each sat is. You want a good, fairly strong, constantly available TP to use for this procedure.
Furthermore, if you haven't read it yet, check this out:
http://www.satelliteguys.us/fta-mpeg2-faqs/190527-how-set-up-motorized-ku-band.html
RADAR