Jumping signal

[lme]

For the last 2 weeks, I noticed a spike (jump) on the signal Q when switching from V to H or vice versa on the same satellite (e.g.15.01db for few sec, & then rapidly down to 14.3-14.5 and stays this way). Initially, I thought it may be due to spring equinox and some flares from the sun, but now is constant, no mater what satellite position the dish is landing.
I disconnected the coax coming from corotor to ASC1 & connected to the box, switching the polarity using ASC1, but the issue is the same. My instalation is: corotor2 with c-band & ku-band lnb, connected with R11 to Ecoda switch; from Ecoda R11 coax to ASC1, then from ASC to Edition.
Any suggestions ?

 

[Terryl]

Sorry for the late response.

One question, how is the system grounded? To the house AC service, a true Earth ground, or not at all?

 

[lme]

To the house AC service.

 

[Terryl]

That could be a problem, the house AC ground is a very big circuit, all the AC outlets and equipment is on one big circuit, I have see ground loops form on these types of grounds, what I recommend for RF systems like satellite service is a metal cold water pipe or a 6 foot ground rod driven in the ground, the the satellite system ground should be transferred to this Earth ground.

The household ground is a very noisy one, every thing in the house that has an electrical plug on it with ground pin makes noise, the further the wall plug is from the AC service entry box ground the longer the ground wire, this makes like an antenna, this can cause all sorts of funny things.

If your water service is a metal pipe try connecting the satellite system to this ground with the appropriate ground connector. (available at most hardware stores)

 

[lme]

At the time when I installed the system (10 years ago), I was in contact with a guy (Brian), from "Titanium satellite" store, who claimed he was installing all kind of satellite systems, & he recomended to connect the ground wire from the dish to the ground wire of main electrical panel of the house, witch in turn is connected to the cold water pipe comming into the house from the ground. I'm not an electrician, but in my view it made sense.

 

[Terryl]

So it's connected to the wire running down to the metal cold water pipe from the electrical panel, then I would check that connection first, as the ground clamp and the clamp connecting the satellite ground age over time it can corrode or oxidize, this can cause problems, a good cleaning of the clamps (with a wire brush) would be a start, then a liberal application of some electrical anti corrosion paste before reconnecting the wires.

This would ensure you have a solid ground for your satellite system.

Now this may or may not be related to the problem your experiencing but it's a good start to finding a fix or possible cause.

 

[lme]

Well, last december I had to fix a water pipe leak right above the meter, so I had to unhook the ground wire witch is clamped under the meeter & above the basement floor, to replace the faulty pipe section. I didn't found any corrosion at the clamps connecting to the pipes. There are 2 clamps: 1 before the meter & 1 after the meter, as the meter body is plastic, but anyway I just
reconnected the ground wire comming from the dish to a cold water copper pipe, just to eliminate this possibility. The issue is still there: signal is spiking couple db above when changing polarity. I looked at the probe inside the corotor to see if the servo motor is jerking when switching polarity, but is no issue there.

 

[Terryl]

Hummmm... Ok try loosing and re-tightening all the "F" connectors in the system, could be something along those routes.

Strange problems...

 

[lme]

Hummmm... Ok try loosing and re-tightening all the "F" connectors in the system, could be something along those routes.

Strange problems...

I will, but my suspicions are now ASC1, or/and a tower at ~1/2 mile. Here is my setup with all RG11 coax connections:

 

[Terryl]

Looks like a solid setup, now one question, is this happening on the "C" band or "Ku" band signals??

If "C" band then I would suspect the tower you mentioned.
If "Ku" band then it could be a local signal like a new airport radar or again looking at that tower, they could have installed a new 5G e TX/RX setup.
If both then it could be that ASC1, this types of problems are hard to track down without specialized RF signal equipment.

 

[lme]

It is happening on C band. Another suspicion I have is about the old original Gold lnb (see attached). It came with the dish I took it from an old person around my area. I can't find any more info about it ! Previous owner had it installed on a polarotor, as I now use it on my corotor. I also have 2 more Norsat: a DRO series & a PLL. The input of DRO is kind of same as the old one & will not help with 5G signals.
The problem with the new series is that I need to use a 45° elbow to mount them on the corotor & install the cover over, so it will decrease the signal quality.

 

[el bandido]

You know, You may just loosen the corotor feed tube and slightly twist the whole feed. That may fix it. Also, the amount of signal you seem to be missing is very small. Hardly worth messing with in great detail. See if the feed needs to be adjusted and also see if something is loose on the dish. Otherwise do not worry about it. A real problem will come along soon enough. My 2 cents...

 

[lme]

You know, You may just loosen the corotor feed tube and slightly twist the whole feed. That may fix it. Also, the amount of signal you seem to be missing is very small. Hardly worth messing with in great detail. See if the feed needs to be adjusted and also see if something is loose on the dish. Otherwise do not worry about it. A real problem will come along soon enough. My 2 cents...

I have the corotor align to the polas axis, using the attached template. I play with it many times, but no joy.