BSC621 signal

[USDownlink]

The signal meter on my Viewsat never seemed to be much more than an "LNB connected' indicator. Generally, it will be at 0 or around 65-70, without respect to an actual signal being present. Probably not news to anyone around here.

So I attach a BSC621-2 I've had sitting around for a while. Never used it. It's not mounted to anything yet, just sitting here on the floor. I get a signal reading of 23-27, on both the Ku and C band outputs. I've never seen this before, and it raises a few questions.

Primarily, is this normal (to have a lower signal level reported) with the BSC621, or might there be something wrong with this one? I'd like to avoid the bother of mounting and trying to align it unless I know it's good.

To double check everything, I grabbed an assortment of other LNBs I have lying around, all kinds, attached them, and saw what I expected to see - signal levels of around 67.

 

[turbosat]

That's prob not unusual , if that lnbf is the one that does circular & linear signals. It's just picking up background noise if it's not aimed at a signal source. What type dish do you have?

 

[Larry1]

The LNBF is picking up noise, and the tuner in your receiver is amplifing the noise by its automatic gain control. This is why an LNBF pointing at the floor is showing a signal level. As to why the BSC621 is showing a different reading, I do not know why, but would not think it is a problem. The automatic gain control will adjust the gain properly once a signal is obtained. This is why it is always best to use the quality meter as a signal guide for pointing. It displays the signal to noise ratio value, but is not consitient between different brands and models of receivers.

 

[Hermitman]

I'm running 2 BSC621s and that number sounds low. If you're using the -2 model, did you remember to reset the LO on your receiver before trying the LNB? That may cause a difference. Good luck.

 

[USDownlink]

Thank you to all for the thoughts. I'll add some additional information based on this...

The LNBF is picking up noise, and the tuner in your receiver is amplifing the noise by its automatic gain control. This is why an LNBF pointing at the floor is showing a signal level.

It's just picking up background noise if it's not aimed at a signal source. What type dish do you have?

Sure. This was indeed my point in describing the signal meter as an 'LNB connected' indicator. I'm not trying to point at anything, yet, although I have recently found myself lucky enough to have come to own an appropriate BUD waiting for a C band LNB.

The automatic gain control will adjust the gain properly once a signal is obtained.

I'm running 2 BSC621s and that number sounds low. If you're using the -2 model, did you remember to reset the LO on your receiver before trying the LNB?

These two quoted statements (seem to) conflict, if one might presumes AGC is always active and is reflected/reported in the signal meter reading. In this case, AGC would account for the behavior of all the other LNB's I attached during this experiment*, all of which settled around 67 on the signal meter while pointed at the floor. The lone exception was the BSC621. I highlight 'once a signal is obtained' however, because no signal is even attempted here. I would be surprised if AGC is selectively switched, but I am admittedly unfamiliar with the architecture of the Viewsat.

At the moment, I tend to believe Hermitman's position that it sounds low. Indeed, I did carefully watch my LO, as I had to change it with each LNBF tried. In the case of the BSC621, 5150 while connected to the C band output, and 10600/9750 while connected to the Ku band output.

-USD

*A standard Fortec single output LNBF, a generic 2 port universal LNBF, a circular reversed polarity dual output Sadoun LNBF, and an Invacom QPH031 (all 4 ports).

 

[glen4cindy]

I'm running 2 BSC621s and that number sounds low. If you're using the -2 model, did you remember to reset the LO on your receiver before trying the LNB? That may cause a difference. Good luck.

Hermitman, I don't think you have enough dishes in your yard.

Seriously, I think my local cable company has fewer dishes than you do!