Too much signal?

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PopcornNMore

SatelliteGuys Pro
Original poster
Mar 20, 2005
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Gibsonia, PA
Is it possible to get too much signal and get unstable video?

When using the Invacom 0.3dB with a 1.2m dish certain channels that have a high signal tend to be unstable and the video breaks up. The highest signal srength on the Coolsat 4000 Pro is 85.

The following channels have unstable video, but have a high signal strength of 83 to 85:
FOX - Beamont
ABC News Now
INFO on AMC3

When using my 0.5dB LNBF on the 1.2m dish the signal strength on these channels is lower (around 75-80) but the video is stable.
 
Weird…..I don’t know

I know ABCNewsNow use to be unstable for a long time but I think that’s fixed. I haven’t had any issues on Fox Beaumont (using a .3 and a 76cm dish)

I assume its possible.
 
I suppose it's possible to overdrive your receiver, but I don't think you're going to do it with that setup.

If you want to, throw an attenuator in line.
 
Your automatic gain control should adjust the gain to compensate for a stronger signal. On the StarChoice (Motorola box) you can view the AGC level. Most receivers will have a minimum and maximum AGC. With a 1.2m dish, you should not reach the upper limit for a signal. If you want to try an attenuator, just put something infront of your LNBF that still lets some of the signal through.
 
A stupid question, but is your dish motorized? I was wondering if you tried bumping your dish a little to decrease the signal just to see what would happen?

It's been a long time ago, but when I worked with RF amps, we'd do a test where the amplifier would be overdriven to put it into compression. The higher the input (after a certain level) the lower the output. I'm not saying that this is what is happening though. Just a thought that I had. I've forgotten so much, and I doubt that it really ties in with receiver design anyway.

It would be interesting to hear what you come up with.

Good luck.
 
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