Need help to identify unknown interference

caramel

Member
Original poster
May 22, 2024
14
14
USA
I've noticed some odd interferences on certain C-band frequencies causing the receiver to lose lock on the transponder. Does anyone know what the possible interference circled in the red box might be? The frequencies displayed in the image are downconverted, and the LNB is a Titanium Satellite - C1-PLL C138 with a 5G filter.
 

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I've noticed some odd interferences on certain C-band frequencies causing the receiver to lose lock on the transponder. Does anyone know what the possible interference circled in the red box might be? The frequencies displayed in the image are downconverted, and the LNB is a Titanium Satellite - C1-PLL C138 with a 5G filter.
Need more information than still screenshots of carriers occurring within the bandpass frequency range of the LNBF.

Are these originating from a satellite? Terrestrial? Duration? Carrier width? Varying amplitude? Modulated? What transponders are affected? Complete transponder loss? Random micro-blocking? Fluctuating loss of decoding?
 
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Need more information than still screenshots of carriers occurring within the bandpass frequency range of the LNBF.

Are these originating from a satellite? Terrestrial? Duration? Carrier width? Varying amplitude? Modulated? What transponders are affected? Complete transponder loss? Random micro-blocking? Fluctuating loss of decoding?
Having the same here on 101. I didn't realize that most of what I recorded today was unwatchble so I wasn't able to monitor it tonight around midnight. on 4180 The SNR stayed around 92% and no BER and the AGC level on the Edision may have dropped under 49

I am a fairly good ways from the closest 5G flamethrower and it's not a direct LOS to the dish at all. I'm thinking maybe an adjacent satellite and a similar carrier coming up at times causing as this is the first time in quite a while it has made things this bad. Guess a good look with the SA is forthcoming.

With as many signals s there floating around these days if we could see em we couldn't see our hands in front of our faces
 
Having the same here on 101. I didn't realize that most of what I recorded today was unwatchble so I wasn't able to monitor it tonight around midnight. on 4180 The SNR stayed around 92% and no BER and the AGC level on the Edision may have dropped under 49

I am a fairly good ways from the closest 5G flamethrower and it's not a direct LOS to the dish at all. I'm thinking maybe an adjacent satellite and a similar carrier coming up at times causing as this is the first time in quite a while it has made things this bad. Guess a good look with the SA is forthcoming.

With as many signals s there floating around these days if we could see em we couldn't see our hands in front of our faces
As noted by others, there was a change in FEC setup on 4180 MHz two or three days ago.
If you have not done so, re-scan this Weigel transponder. I find that it is now considerably stronger
in quality reading, and all channels have returned.
 
Thanks for the info on the FEC rate change I wasn't aware of that one.
I went ahead and disassembled the unit and didn't see anything obvious except maybe a couple of solder joints at the board for it was questionable. I cleaned off the old hard heat sink compound from the processor and heat sink and replaced that with new product. Out of Arctic Silver so it got the regular white version. I've used it on transmitter pa applications and had good results. Thanks again for the heads up
Wt
 
Still having problems with this particular carrier. Seems worse in the day time hours but I'm getting 92% CNR at both time slots.
I've noticed similar problems on a couple satellites. One of them will play fine all day, and then start acting up toward evening. On the other one, about half the channels will drop clear out.

A few hours later, they'll be back. I almost deleted them once, thinking they had moved or changed transponders.

When they're on, they have a 95/85 signal level. I did move a 10 footer when Le Sea left, rolling it down to 127W so the wife can watch Reelz.

It was cutting up something fierce on the 7 1/2 footer. I also also rolled the 97W dish down to take the place of another 7 1/2 footer.

The selection gets smaller by the day. Before long, I may have a lot of scrap aluminum laying around. They just installed fiber on our road and we're waiting for them to hook it up and test it.

I really don't need a half a gig, but I'm taking it and their phone service. It should be operational sometime next week.
 
IMO, that's a clear sign of intermittent 5g interference.
Another possibility is a drifting LNB or LNBF. Could be temperature sensitive, but more likely would be the LO drifting when the LNB/LNBF is directly in the sun. Take a small plastic garbage can and slide over the device, and see if the problem goes away. If this is the cause, it is either LNB replacement or in the case of super sensitive and weaker signals, cover everything. If you have a dark colored weather cover, paint it flat white with a spray can. One can often duplicate thermal drifting problems by getting a hair dryer close, but not too close, to the electronics and see if things drift. Before spending any money on filters or anything else, check out the above basics---old electronics is often not stable enough to deal with DVB-S2 digital signals. Good luck.
 

Lesea Feeds Gone

CBand 10ft Dish setup question