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Help With Satellite closet

Posted: Fri Apr 02, 2010 6:42 am
by johnshaw
I'm hoping someone has experience with a Sattelite Closet configuration. In my Stake Center, there are two channels in the internal Audio/Video system. Channel 3 is our Feed from the Sattelite, and Channel 12 is the feed we have for the chappel system with a video input.

In the Satellite closet, I see 2 RF outputs on the bottom of the unit, which I can plug into and test just fine, I see both Channel 3, and 12. Next to these are 2 composite outs labeled Video and Audio. Does anyone know what those are supposed to do? Or what they are for? Basically I'm looking for the right place to place my webcasting equipment, and I'd much rather take the video feed from composite than to take the RF and convert it. It seems to be the only place I have a composite output.

Suggestions?

-John

Posted: Fri Apr 02, 2010 11:16 am
by russellhltn
jshawut wrote:Next to these are 2 composite outs labeled Video and Audio. Does anyone know what those are supposed to do? Or what they are for?
I'll have to look at ours, but I think that may be the outputs from the VCR. I'm not sure under what circumstances they would be used. Perhaps for tape duplication?

You can probably use them, but the VCR will have to be on and any status messages from the VCR will wind up in your feed. Also, depending on how you've set the VCR, it may be doing the RF conversion anyway.

Also, I suspect that the only way to get the chapel video with the existing setup is to demodulate Chanel 12. I think you'll find the camera line comes in and goes straight to the modulator. It does not go to the video distribution amp, so there are no taps that can be used.

Satellite closet

Posted: Sun Apr 04, 2010 9:08 pm
by Paulbb1
You are not clear but I assume the video is a camera video coming from the overflow area RCA jack. The video is composite from the camera? Our camera outputs composite and s-video. The composite signal will feed the entire building if connected to overflow area RCA connector. It is meant for a camera input.

If it is like our cabinet the camera video goes to one of the two Pico PCM55 Audio Video Modulators channel 12 in your case. This is a composite signal. The audio input is from the sound system of the building. This is where it was recommended to me by our third party person who install and maintain the building systems for FM office. Our feed from the building was cut and two generic blade female connectors were crimped in and then connected to the modulator. Original installation setup. We take the sound from here to the video capture card. They converted to RCA connectors to make it easy to use. A 'Y' adapter RCA ends could also be used before the modulator.

It has a tenancy to over drive the sound during encoding and at the receiving end. An attenuator might be need to bring the sound level down.

There is more to be discussed. Check out some of the discussions on configurations. Ask more questions and be careful o which video capture card you use.

I stand corrected. RF signal carries the composite signal per my electrical engineer.

"RF is anything in the spectrum of about 1MHz to into the GHz range. Composite video is baseband signaling that contains the video and audio (composite) signals. An RF carrier (say channel 3) is modulated with the composite video/audio to create a signal that can be received by a TV."

The key words here to me are 'modulated ... create a signal that can be received by a TV.' Video from a camera has no TV channel information so it can be selected. It has to go to the TV RCA video input of a TV. I will understand this all some day.

I hope this will help.

Posted: Mon Apr 05, 2010 1:04 pm
by johnshaw
PaulBB1 wrote:You are not clear but I assume the video is a camera video coming from the overflow area RCA jack. The video is composite from the camera? Our camera outputs composite and s-video. The composite signal will feed the entire building if connected to overflow area RCA connector. It is meant for a camera input.
Yes, this is exactly the setup that I will be using
It has a tenancy to over drive the sound during encoding and at the receiving end. An attenuator might be need to bring the sound level down.
This is what I have found to be the case. As I bring the RF into a VCR, and then use the RCA output to the webcaster, the sound level comes through extremely distorted. To test this I purchased a cheap sound volume control mixer at Radio Shack, I found that I could come out of the VCR, into the mixer, lower the input levels, and then out to the webcaster, the sound is much better, however, there is still a hum, which I am trying to get rid of with a 'HUM Eliminator'. Haven't finished that testing yet.

My big question is that I seem to have a RCA composite video and audio output at the satellite closet that doesn't seem to be connected to anything? I was hoping that others have a similar setup. If I remember I'll grab a picture that I can attach.

-John

Posted: Mon Apr 05, 2010 2:03 pm
by SheffieldTR
The hum is usually a ground loop hum and can be eliminated a number of ways, from a ground loop interrupter (Removes the ground prong by going from 3 to 2 prongs) to changing the outlet that the communicator is plugged into. I know one person who cut off the third prong and that worked for them. Not sure I would recommend that option though.
Troy

Posted: Mon Apr 05, 2010 2:12 pm
by russellhltn
jshawut wrote:As I bring the RF into a VCR, and then use the RCA output to the webcaster, the sound level comes through extremely distorted. To test this I purchased a cheap sound volume control mixer at Radio Shack, I found that I could come out of the VCR, into the mixer, lower the input levels, and then out to the webcaster, the sound is much better
What is the webcaster input? Mic level? Is there a line level input you can use instead? I think that would help with the hum. I'd expect the output from a VCR to be level-compatible with any computer line-in without distorting.

Posted: Mon Apr 05, 2010 2:24 pm
by russellhltn
tsheffield wrote:The hum is usually a ground loop hum and can be eliminated a number of ways, from a ground loop interrupter (Removes the ground prong by going from 3 to 2 prongs) to changing the outlet that the communicator is plugged into. I know one person who cut off the third prong and that worked for them. Not sure I would recommend that option though.
Troy
While removing the 3rd prong of a AC power line is a quick and dirty fix by many a audio tech, it's not something I'd recommend because of the safety issues. The safer fix is to insert something in the audio connection to open the ground. Usually a transformer or some variation.

If the audio is 3-wire, one can safely lift the audio ground line. However, since the source is a VCR and going to a computer input, I don't think that applies in this case.

Posted: Mon Apr 05, 2010 2:53 pm
by danpass
jshawut wrote:My big question is that I seem to have a RCA composite video and audio output at the satellite closet that doesn't seem to be connected to anything? I was hoping that others have a similar setup. If I remember I'll grab a picture that I can attach.
Assuming the body of the cabinet has a rear hinge, you should be able to swing it out(*) to gain access to the rear panels of the devices that are mounted in the cabinet and view the cabling. If you do this, you should be able to see if the connectors you are wondering about are connected internally and if so, follow the cables and determine to where they run.

(*) In case anyone reading this is unaware, when the cabinet door is open, two slotted bolt heads are exposed, one at a top corner and the other, at the bottom corner directly below. These bolts secure the cabinet in the closed position. Turn both heads counter-clockwise until each bolt is loose. You should then be able to pull that side of the cabinet away from the wall. In some cases, it helps to lift on the cabinet a little when pulling it away from the back as well as when closing it back up again. (Most readers are probably aware of this already. The A/V person that preceded me was not. When he made equipment changes, he did it all by unscrewing blank covers and reaching through the openings and feeling around, when disconnecting and reconnecting cables. :o )

Sound over driven

Posted: Mon Apr 05, 2010 3:12 pm
by Paulbb1
Try taking the sound from the building input to the modulator for ch 12. Put a Y in the coaxial cable by converting the f-connector to RCA and then to a Y and a f-connector to RCA converter on the modulator input. Maybe the hum will go away then. Ours was already converted to RCA. But, it also had a set of blade connectors to take the sound out. This avoids the use of the VCR output.

The driver software for the capture card Osprey 210 allows the lowering the input to the encoder SW. If it doesn't work I will use an attenuator that was recommended to use. I will get the specs and post it here.

Image of Satellite cabinet

Posted: Mon Apr 05, 2010 4:01 pm
by Paulbb1
Note the red RCA cable plugged into the sound input of the video camera modulator. Ours is ch 5 yours ch 12. It has an adapter that goes from RCA to f-connector of the modulator See the two red red blade connectors for taking sound from the building sound system. We plug those into the sound in on the computer video capture card. This is the original installation.