terrestrial interference?

[truckracer]

For some time now, every morning between 11:00 am and noon, I get digital breakup on all my western most sats with 4dtv (c-band of course).

I am thinking i have TI.

I have strong signal quality, but it blips out.

On analog channels you can see little surges of sparklies when it happens.

THis does not affect KU band.

I live near a river where we have riverboat traffic. Do they have radars that can interfere with c-band?

 

[cybertrip]

There are C-Band weather radars. I think there are also C-Band microwave transmitters as well.

 

[Wholeshoe]

If it is radar you should be able to time the interferance on your watch. IE you will see breakup every 2 min or so or however long it takes the interfering radar to make its sweep.

 

[1inabillion]

Its been reported on other fourms about digital breakup so your not alone

 

[iammike]

Hey Trucker,

I grew up about 120 miles or so north of you along that same river. I don't think the boats would have any radar that would affect your reception. Back home, the biggest concern they had was keeping the barges in the channel dredged out by the Corps. of Engineers. I'm thinking they'd probably have a pretty sophisticated depth finding system, but can't see it affecting your satellite reception. At least, I never heard anything about river traffic affecting reception.

Since it's happening during a specific hour each day, I'd be more suspicious of local land-based industry. Back home we had a lot of chemical plants around. Any chance a plant, or maybe a power generating station nearby could be causing it?

Mike

 

[cybertrip]

Unlikey. Power generally causes interferance in the lower HF frequencies in the MHz and not the higher frequencies such as satellites in the GHz.

 

[truckracer]

timed the TI

It does occur every 1 minute 20seconds =/- 2 seconds.

It must be some type of radar. affects c-band only-even analog!

 

[1inabillion]

It does occur every 1 minute 20seconds =/- 2 seconds.

It must be some type of radar. affects c-band only-even analog!

I live in the midwest and we all have digital breakups too some speculat`s its may be AWACS you can google it

 

[N4ST]

Can't help you, but here's a related funny story.

When my family first got DTV it seemed like every time we bought a pay-per-view movie the first couple of minutes would be corrupted. We would get perfect reception and then loss of signal during the beginning of our movie. Just figured it was a bug in their PPV delivery system. Until my youngest son noticed that our loss of picture coincided perfectly with using the microwave to pop the popcorn for the movie! (The dish was mounted outside the wall about 4-feet from the back of the microwave) New microwave and the problem went away.

 

[truckracer]

My microwave was not on, but who knows my neighbor could have some RF leaking from his..

 

[Hermitman]

At that rotation speed, it's too slow to be an aviation radar or AWACS. However, there are some slow rotating weather doppler radars. It may be your local National Weather Service doppler radar or local TV station radar is being calibrated every day at the same time and as part of the calibration, the operators lower the radar beam to a below-the-horizon angle causing your interference. You might want to call around and see if any weather radars are being checked at your interference times.

 

[1inabillion]

The Model 7893D-3400/4200

Extended C-Band Filter is an "International" version of our model 7893D bandpass filter. This "extended" C-band bandpass filter can be used globally, where there is access to the wider [ 3.4 - 4.2 ] GHz satellite band, and like the 7893D, this filter offers super-selectivity by virtually eliminating all out-of-band interference - such as military radar.

You can`t rule out anything even AWACS when it comes to Ti

 

[Hermitman]

With all due respect, I do not believe this can be AWACS. AWACS' rotodome rotational speed in the transmit mode is 6 RPM. So any interference should occur every 10 seconds. And if for some weird reason the operators were transmitting in the idle mode, the interference would occur every 4 minutes due to a 1/4 RPM rotation speed at idle. Even if they were on the ground doing a "live fire" every day at the same time, the rotodome is stationary and the beam is pointed upwards into space so not to cause interference or set off ejection seats. And while I'll agree a bandpass filter would curtail any out-of-band interference, if its coming from in-band, the source needs to be found and fixed. In such a case, a spectrum analyzer would be helpful to point out the frequencies causing trouble.

 

[Stefan]

The Model 7893D-3400/4200

Extended C-Band Filter is an "International" version of our model 7893D bandpass filter. This "extended" C-band bandpass filter can be used globally, where there is access to the wider [ 3.4 - 4.2 ] GHz satellite band, and like the 7893D, this filter offers super-selectivity by virtually eliminating all out-of-band interference - such as military radar.

You can`t rule out anything even AWACS when it comes to Ti

Actually, if your gonna use a filter and you have reached the conclusion a filter is what you need, you should probably go with the regular 7893d and not the international version. Remember the whole point of a bandpass filter is to reject out of band interference. Therefore you only want it to freely pass the frequencies your interested in receiving which in North America is going to be 3.7 to 4.2 Ghz. If it just so happened that the offending signal was in the 3.4 to 3.7 range the international version would do nothing for you.

Of course first you probably need to determine what the frequency of the offending signal is and if possible the general direction it's coming from. If it's in band interference a bandpass filter will likely be useless and seeing as how they cost in the $400-$500 range, youd likely want to find this out before purchasing one. As Hermitman mentioned a spectrum analyzer is what will be needed to do this. If you don't have one yourself and don't want to purchase one, perhaps you could find someone who installs dishes in your area who has one and might be willing to come out and take a look at the problem.