Film-Tech Forum ARCHIVE: Satellite GE-8 Being Subjected to Solar Flare Tests?

This is topic Satellite GE-8 Being Subjected to Solar Flare Tests? in forum Film-Yak at Film-Tech Forum ARCHIVE.

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Posted by Paul G. Thompson (Member # 655) on 02-15-2004, 12:52 PM:

An extreme phenomena has been driving out GE-8 reception absolutely nuts lately - just like clockwork. The last three nights at precisely 1900 hours Pacific Standard Time, the AGC on the Starguide III receivers go beserk, accompanied with fault lights and audio drop outs.

GE-8 is our Satellite Music Network which is controlled by ABC. We also get our news feed from that service. It got bad enough last night where we had to over-ride it to local broadcasting.

What is happening, I really don't know. ABC says there is nothing wrong with the uplink. (of course....even if their uplink was bad, the fault lights would not flash)

This phenomena lasts for about 1 hour and then it clears up and normal reception is achieved.

This same thing happened on a couple of occasions within the last year or so. The last time it happened, it was at almost exactly 1200 hours Pacific Daylight Savings time.

Nobody has any information as what the heck is causing it, or if they did (which I don't know) they don't want to talk about it.

Any ideas? I thought some of our jammer aircraft were playing around, but the local air base has indicated, "It was not them."

Shortly after 9/11, there was a few days where I observed an AM station blackout on a certain frequency. The station I was listening to was blotted out by a powerful steady audio tone of about 1 khz.

Any guesses?

Posted by Mark Gulbrandsen (Member # 72) on 02-15-2004, 01:54 PM:

I'll laugh out loud when this happens to some important D-Cinema down link [Big Grin]

..... I bet all they'd get is bars and tone!

Mark @ CLACO

Posted by Tim Reed (Member # 137) on 02-15-2004, 03:04 PM:

quote:
at precisely 1900 hours Pacific Standard Time, the AGC on the Starguide III receivers go beserk, accompanied with fault lights and audio drop outs.

Great! My experiments are working! [evil]

Posted by Floyd Justin Newton (Member # 1316) on 02-15-2004, 03:16 PM:

[Big Grin]

UFOs?!

fjn

Posted by Paul G. Thompson (Member # 655) on 02-15-2004, 04:34 PM:

Well, I asked for guesses, so I got some. [Big Grin]

Posted by Paul Mayer (Member # 355) on 02-15-2004, 04:45 PM:

Hmmm. It's a little too early for eclipse season and sun outages just yet.

What are your antenna look angles? Weather along the link path? Polarization? Digital or analog multiplexed downlink?

I see GE-8 is a C-band bird with 24 on-line (and 8 backup) 20W SSPA transponders using good ol' linear H/V polarization. It's parked at 139°W longitude. Rain attenuation along the downlink path can be a problem if there is a big storm on the path with a low elevation look angle. But from your location to 139°W the vertical look angle isn't low (about 48° right?). And C-band w/linear polarization isn't nearly as bad as Ku-band w/circular when it comes to rain fade issues. So probably not rain fade...

ABC claims their uplink is OK (of course they always will).

Are other stations using the ABC downlink reporting problems?

Have you got punctual birds or squirrels nesting in your LNA/LNB/polarator assembly? [Smile]

Temperature-related issue developing at the antenna or downconverter?

Here's a long-shot SWAG (scientific wild ass guess). Right now GE-8's controllers would be reconditioning its batteries in preparation for the Spring eclipse season. Wouldn't surprise me to find that the payload bus voltages could sag enough during reconditioning to degrade SSPA performance, especially if there are battery degradation issues (of course that's not supposed to happen, but it can). But GE-8 was launched in December 2000 so there shouldn't be any power subsystem issues yet (unless Lockheed Martin had a bad battery run like Boeing Satellite Systems had a few years back). A quick look shows no space industry news releases about GE-8 after its launch so its AS 2100 bus is probably just fine.

Posted by Bruce Hansen (Member # 281) on 02-15-2004, 05:41 PM:

7PM? Is this when everyone is using the microwave to heat up their dinners at your place? Or has ABC's microwave broken, and everyone is putting their dinners in front of the uplink dish to heat them up? [Big Grin]

Could there be any local interference? TV news ENG links? Or a delivery truck parked in front of your dish?

Posted by Paul G. Thompson (Member # 655) on 02-15-2004, 06:12 PM:

You guys crack me up. [Big Grin]

Paul, I don't know if it is a problem you describe. But I have not heard anyone else squalking about it. It does seem kind of odd that it occurs at almost exact times.

A soothsayer that runs the local inconvenience store mentioned there is equipment aloft that will detect the solar disturbances and face the bird the other way. I wonder if they might be testing the system?

Now, the soothsayer that runs the inconvenience store has a friend of a friend of a friend's friend who is in the business of the friend's friend. [Big Grin]

Anyway, I am going to try to get to the bottom of this somehow. [Smile]

Posted by Paul Mayer (Member # 355) on 02-15-2004, 06:37 PM:

A "soothsayer" ey... [Smile]

There are some configuration things that are sometimes done aboard 3-axis stabilized spacecraft to deal with solar phenomena but these will not routinely affect the communications payload. They certainly wouldn't just point the spacecraft off of their footprint while there are paying customers using it. In fact, testing of any kind is generally not allowed on an active spacecraft--the business repercussions of an "off pointing" incident being decidedly unpleasent. These things usually involve clocking the solar array panels to reduce the torques that would otherwise build up during solar wind bursts. Even though the solar "wings" are no longer perpendicular to the solar radiation, the resultant drop in spacecraft bus voltage is not enough to affect the payload.

On spacecraft that have degraded power subsystem performance there will be a planned sequence for "load shedding"--they will turn off selected SSPAs during the degradation period (usually during spacecraft eclipse) to keep the load from collapsing the bus entirely. But these planned shutdowns will be negotiated ahead of time with each of the affected uplink customers and written into their contracts. That way the customers can have backups ready to go. So unless this is some kind of new spacecraft anomaly that they're just now getting a handle on, you would have heard about it from your uplink provider.

I have seen some pretty strange things affect spacecraft TTAC links over the years. Would get occasional long bursts of noise on telemetry lines from certain antenna sites. In one case it was traced to cows rubbing themselves against the telephone poles that were carrying our circuits to the site--the vibration was enough to put noise on the circuit and disrupt our modems. [Smile]

Another one was found right inside our control center at the phone company demark--straps on the punchdown block were working loose because they were being heated by the afternoon sun each day. Push down on them with a thumb and voila--no more noise. [Big Grin]

Space can be a funny place sometimes.

Posted by Paul G. Thompson (Member # 655) on 02-15-2004, 07:08 PM:

Paul, I am with you on your signature.. I need a F****** drink! [Big Grin]

All in all, It is perplexing. Josh's radio stations are on the same bird. I'll have to ask him if they had any problems. If not, it is probably man-made by the crews screwing around with the jamming equipment used in some of the NAS Whidbey aircraft....or some other military facility.

Reports came to me there was an aircraft buzzing the sky at the time this happened last night. I don't know what kind of an aircraft it was, but maybe it was just a coincidence.

Thank you for your input. [Smile]

I have to admit...I have had some "punch block" issues now and then...Jeeze, I hate those things, especially when they go HS on me..and they seem to do that in the middle of a crucial broadcast. [Mad]

Posted by William Hooper (Member # 71) on 02-16-2004, 12:31 AM:

The precisely 1900 hours thing is interesting. Is there a nearby bldg with microwave or satellite arrays? Is somebody blasting an upload of something everyday at that time?

Posted by Paul G. Thompson (Member # 655) on 02-16-2004, 01:38 AM:

William, that is an interesting point. However, as far as I know, the closest thing is the communications equipment on Burlington Hill, Little Mountain, and Mount Constipation. None of those facilities have uplinks that I know of.

Other than that, NASW has some very huge "Sunflowers" planted near the beach front and they point in all different directions. Some of those things must be at least 50 feet in diameter....

Posted by Bruce Hansen (Member # 281) on 02-17-2004, 05:30 PM:

The Martians are getting back at us for cluttering up their planet. [Big Grin]

Posted by Josh Jones (Member # 447) on 02-17-2004, 10:27 PM:

we've not had any problems over here at that particular time of day, but i dont think we have any shows that run at that time either off that bird. We do have more problems with aircraft flying over, knocking out the signal and making the on air burp.

I could be possible that people are jamming at that frequency for whatever reason.

Josh

Posted by Gary Crawford (Member # 2038) on 02-18-2004, 12:43 PM:

Even if the arc of birds ran across the Sun solar outages only last maybe 7 minutes if that. Any geosync bird is about 22,500 miles out and 7 minutes is the max I experienced.

As far as uplinking, which I also do, I'm still transmitting during sat eclipses, I just watch on the spectrum monitor as the cute little vertical lines go down to flatline for a few minutes and then back up.

When it is solar outage time, the first thing I do is take the phone off the hook. The downlinks still don't understand the phenomenom.

Sounds like something is jamming you or stepping on you. Analog might be a little forgiving but I presume this is digital compression you are taking down. DC is very low powered (I'm running 19 watts up on Galaxy3C right now) and we used to run 75-100 or more back in the analog days. If someone is firing a high-powered analog up there the DCs will get knocked off.

Posted by Paul G. Thompson (Member # 655) on 02-18-2004, 07:19 PM:

We have not yet found the source of the problem. However, I think I have to agree...we are experiencing a local man-made interference. By whom or why - that's anybody's guess.

Posted by Jack Ondracek (Member # 1466) on 02-20-2004, 01:20 AM:

Turn off all your wireless phones, Paul. [Big Grin]

Seriously... since I moved here in '86, we've had more than a few "unexplained" interference phenomena... all of which have been blamed on the Navy, their radars, "secret facilities testing", etc... none ever proven, of course. It didn't help that most of the local managers blamed ALL of their technical problems on the Navy... including the fact that their 1,000 watt signals didn't cover all of King and Pierce counties (Seattle, Bellevue, Redmond, Tacoma, etc).

One of the more interesting events around here was when almost ALL keyless auto locks in the area ceased to function for a couple of days. The local auto dealers went nuts trying to figure out what happened and how to fix it... the Navy denyed culpability, and the FCC, while making a point to visit in their big white van, said nothing. The problem went away and never returned.

Posted by Paul Mayer (Member # 355) on 02-20-2004, 09:20 PM:

Now Las Vegas, NV gets to join in on the "key fob remotes don't work" thing. All over town today, people are reporting that their car key lock remotes aren't working. Wish I still had my old IFR RF spectrum analyzer.

Probably the spooks up at Area 51 playing around with some new toys... [Smile]

Posted by Gordon McLeod (Member # 33) on 02-20-2004, 09:59 PM:

Paul it must be one of the switcher rectifiers in those strong consoles at whidby island creating the RF [Big Grin]

Posted by Paul G. Thompson (Member # 655) on 02-20-2004, 10:09 PM:

I don't know, Gordon. [Big Grin]

Anyway, whatever the problem was, it went away by itself.

But even though, I am still going to look up in the dish's schnozola and see if anything might be fouling the probe.

I don't think I will find anything....the AGC is well within recommended reception and is steady as a 100-ton rock and has been for the last several days.

Posted by Bruce Hansen (Member # 281) on 02-24-2004, 05:46 PM:

I notice you said the problems happened at 7PM and 12PM. What time is your local TV news? Did you notice if there was a live shot on the news from the same place on the days you had problems? Some of the microwave systems that are used to do local live shots can screw with sat downlinks.

Posted by Paul G. Thompson (Member # 655) on 02-24-2004, 06:49 PM:

Hmmmm...very interesting, Bruce. I'll have to check on a correlation about that. But since I brought this topic to the floor for discussion, we have had no problems whatsoever. We are mystified about it.

Posted by Floyd Justin Newton (Member # 1316) on 02-25-2004, 07:33 PM:

[Confused]

--UFOs?--

fjn

Posted by Bruce Hansen (Member # 281) on 02-26-2004, 06:24 PM:

The path of the microwave beam from the remote truck to the station (or transmitter site, which is sometimes used due to the tower being a good high receive site for the live shots) may cross your dish, depending on the location of the live shot.