Coax to composite or component?

[heathmc]

Hello, I am trying to set up a small home theater system. Right now it requires a A/V switch ( a cheap 4 input HD selector) , which is fine. However there is no input for coax so I have to convert the coax to either composite or component, (I don't have HD channels so either is fine). I thought this would be easy using and older vcr/dvd player with coax in and composite out, but I only get sound not video. I am trying to keep this cheap because it is for a college room so I don't want to spend a fortune.
TL;DR: I need something to turn the cable coax into composite or component. I tried a vcr/dvd coax input and composite out, but I got not video.

Thank you so much for your help!

 

[TLS Guy]

Hello, I am trying to set up a small home theater system. Right now it requires a A/V switch ( a cheap 4 input HD selector) , which is fine. However there is no input for coax so I have to convert the coax to either composite or component, (I don't have HD channels so either is fine). I thought this would be easy using and older vcr/dvd player with coax in and composite out, but I only get sound not video. I am trying to keep this cheap because it is for a college room so I don't want to spend a fortune.
TL;DR: I need something to turn the cable coax into composite or component. I tried a vcr/dvd coax input and composite out, but I got not video.

Thank you so much for your help!

Your post is confusing to say the least.

You need to define what you mean by cable coax. A coaxial cable is just one which has a center core conductor, the insulation layer, the grounded screen and then the jacket.

These cables can carry a variety of analog and digital signals.

So I need to know exactly what the specifications are of the output you wish to convert to analog composite or component.

So exactly what devices are you trying to connect and from what outputs, to what inputs?

I suspect you are dealing with a digital signal and want an easy way to convert it to analog. This is not going to happen without some type of DAC and, even then you will likely run into a road block because of DRM.

An old VCR will have the old analog inputs for an antenna or old time cable. These standards are no longer in use and not legal. So I suspect that is why you got no picture.

 

[heathmc]

I'm sorry for the confusion, the coax I am referring to is my cable tv. It comes from the wall and I need to convert it to composite or component. This cable is the basic cable that the college offers, I only assume it is old time cable (they get no HD).
So is that impossible? Because like I said the vcr gives me audio output from the cable but no video it's really weird. Thanks for the fast reply.

 

[Adam]

TLS is asking the right question - do you know if your dorm's cable system is analog or digital? I can't imagine that it's not analog, though, because you should haven't gotten anything at all from that VCR if it was digital. I wouldn't be surprised if your dorm is still carrying an analog cable line.

In the past, I have done exactly what you want to do. When I lived in a dorm, I used a VCR as my TV tuner and had it hooked up to a stereo receiver and a small monitor. I bought an old VCR from a guy for $10, but it didn't end up working, and my parents got my one for Christmas.

What do you have the VCR connected to?

 

[TLS Guy]

TLS is asking the right question - do you know if your dorm's cable system is analog or digital? I can't imagine that it's not analog, though, because you should haven't gotten anything at all from that VCR if it was digital. I wouldn't be surprised if your dorm is still carrying an analog cable line.

In the past, I have done exactly what you want to do. When I lived in a dorm, I used a VCR as my TV tuner and had it hooked up to a stereo receiver and a small monitor. I bought an old VCR from a guy for $10, but it didn't end up working, and my parents got my one for Christmas.

What do you have the VCR connected to?

I suspect it may be digital now, even if SD. We are well past the analog sunset.

The University will be getting a digital signal for sure now. So the issue is exactly what type of signal is at the wall, and if analog, if it needs some type of decoding.

He needs to ask these questions to admin.

 

[Adam]

I suspect it may be digital now, even if SD.

If it is, then the VCR has an ATSC tuner in it - because no NTSC tuner (as far as I know) is going to extract audio from a digital signal.

To the OP - all you want is a TV tuner, right? The VCR is a good approach, assuming that it has the tuner that you need (NTSC and/or ATSC). The fact that you get audio tells me that your tuner is working - now it's a question about why the video isn't working. It might be in how you have it set up, or it might be a problem with the VCR, video cable, or monitor. We can step through this and see if we can get you all set up.

 

[heathmc]

Thank you again, I am not in a position to get the SN off the VCR right now but I will post it when I can. I also sent and email to the school asking if it is digital or analog and was post that also. Here it the current setup it is slightly confusing so bear with me. First the TV, it is a LG flat screen with no audio out, and 1 component input. The sound, there is an audio receiver with a 5.1 setup. Devices to hook up, 1 3.5mm jack for ipod (done, works fine), and xbox, wii and cable. To do that I purchased a 4-Way Manual High Definition Audio/Video Selector Amazon.com: Philips SWS2325H/27 4-Way Manual High Definition Audio/Video Selector: Electronics

The cable from the wall goes into the VCR and the output goes to the A/V switch.
You can see in the picture input one (on the A/V switch) is SD that is what the VCR's output goes to, the xbox's component into input 2 on the A/V switch and the wii to input three. From the A/V box it's component video out goes to the tv and the audio out goes to the audio receiver.

Since I get video and audio from the wii and xbox, but only audio from the vcr I thought it could be the video cable but I replaced that and still the same problem.

 

[BMXTRIX]

Agreed! There are many different things which could impact what is causing you grief on this.

1. What does the college say you need for a TV? Does it need a NTSC tuner? ATSC? QAM? Pretty much all new TVs have a QAM tuner for free-and-clear digital channels including HD channels.

2. Your setup, as you describe it, makes almost no sense. Specifically: "Right now it requires a A/V switch ( a cheap 4 input HD selector) , which is fine" - You can't just mix and match component video with composite video. Most home theaters use an A/V receiver, and cheap ones don't convert from composite to component.

3. You SHOULD try the absolute easiest setup first. If you have a VCR which is decoding the analog audio on the red and white RCA connectors on the back of it, then connect the YELLOW wire (composite) directly to your TV's composite (yellow) input. Make sure the TV is on composite video, then see if you get an image to go with the sound. You really should. If you do not, then there are any number of reasons why you don't... A bad cable, a broken VCR, a bad cable feed from the wall. If you stick a VHS tape in the VCR can you playback and does it send audio and video out properly? If it does, then the cable feed from the wall may be bad. If it does not, then it may be a bad output or a bad cable with the VCR. If you can get one, try hooking up a smart phone or DVD player using composite video cables to the TV. If NONE of them work, then something is screwy with your TV or your setup.

I would like to hear a better explanation of the exact signal pathway with your VCR setup as it is, and it seems like you are working in a standard definition TV (SDTV) location. This is unusual as almost all of the rest of your stuff will likely be HDMI or component HD video. So, if this is the case, then you must have a composite video path to your display or use something which will convert it from composite to component video. Note: A cheap switcher will NOT. A cheap receiver will NOT.

 

[Adam]

You can't just mix and match component video with composite video.

Agreed - I think that's the ticket right there. I don't see in the instructions for that switch where it mentions if it will or will not convert, but my guess is that it won't. Of course, if the Wii is connected using a composite video cable, then I'm wrong.

So, are the Xbox and Wii both connected using component video cables? Is so, does your LG TV have a composite video input? If it does, you could connect the composite video output from your A/V switch to that composite video input.

Another option would be to run the coax cable to both the LG (assuming it has an NTSC tuner) and the VCR, let the LG decode the video, and use the VCR to send the audio to your receiver. You'd have to check if the audio and video are in sync using that approach, but it might give you better video quality because you aren't going through the VCR and a composite video connection.

 

[heathmc]

3. You SHOULD try the absolute easiest setup first. If you have a VCR which is decoding the analog audio on the red and white RCA connectors on the back of it, then connect the YELLOW wire (composite) directly to your TV's composite (yellow) input.

The problem there is the TV does not have a composite (yellow) input... =(
So what I am gathering is that I now need something to convert composite to component so the A/V switch works. Is that right?

 

[markw]

Let's start at the beginning.

Your cable TV is ,for all intents and purposes, some sort of radio frequency signal,, be it digital or analog. It doesn't matter.

This is a totally different creature from a video signal, be it composite of component.

To convert that RF signal to a video signal, you need some sort of device, which type is yet to be determined. A simple cable with different ends won't do it. That would be like connecting an FM antenna to the input of an audio amplifier and expecting sound. ...ain't gonna happen.

Now, if the university sends out an unencrypted analog signal, any functioning VCR or TV will work. It won't be hi def but, hey, who cares?

If they send out an unencrypted digital signal, any TV or VCR with a QAM* tuner will work. I can't recall any VCR's with that, but I could be wrong.

If they send out an encrypted signal. either analog or digital, you're probably gonna need some sort of set-top box in order to get a picture.

'effens I were you, I'd check with the powers that be to see exactly what you need to do what you want to do. Once you find that out, perhaps we can provide some guidance instead of playing battleship.

And, no, composite and component are not interchangeable on a switch.

* QAM = digital cable TV tuner. ATSC = digital OTA (Over The Air, or antenna) tuner

 

[Adam]

Btw, which A/V receiver do you have? It might be able to do the composite-to-component video conversion for you (and the video/audio switching, as well). If you're uncertain about its capabilities, you can let us know the model number and we can check it out for you.

 

[heathmc]

Unfortunately Adam it does not have that ability, it's only composite in composite out. For now I will just plug the cable into the tv and get crappy sound. But continue the current setup for the laptop/xbox/wii. I will tell you what the school said as soon as I hear!

 

[markw]

I assume the TV doesn't have a red/white analog audio output. Does it have a headphone jack?

 

[MDS]

Nobody has mentioned the fact that you often need to switch inputs on a VCR to have it send the RF signal from the coax input to the composite video output. It's often labeled 'TV/VCR'.

Also you may need to tune the VCR to channel 3 or 4.

 

[heathmc]

markw The tv is really weird, it only has 1 hdmi in,1 component in and no composite and also no audio out. It does have a "service jack" but I don't know what thats for.

MDS, I have tried that but still no video

 

[Adam]

Nobody has mentioned the fact that you often need to switch inputs on a VCR to have it send the RF signal from the coax input to the composite video output. It's often labeled 'TV/VCR'.

A great point in general. The OP said that the audio worked, so I believed that was not the issue and didn't mention it.

 

[macddmac]

A used terestrial qam tuner might work for you. I have a Samsung model that I used to feed the raw Comcast feed into and it gave me all the unscrambled channels to my panny monitor via component or hdmi.

 

[BMXTRIX]

Heath - Make and model of your TV please.

Whenever possible, provide a make a model, not just a brand. LG makes about 100 different TVs right now - plus previous years TVs.

It is extremely rare for a TV not to have a composite video input, but they are often combined (these days) with the component input.

IF THAT IS THE CASE (composite on green for example)....

Plug the output of the VCR into the 'GREEN' connector on your Phillips switcher, not the yellow connector.

Now, your TV remote should allow you to switch to 'AV In - Composite' or something similar. It may say "Component" for Green, Blue, Red (Y/Pb/Pr) connections, and something like AV or Composite for when it is using the green connection for composite video. Typically composite is yellow, but with fewer and fewer of us using composite, that is going away.

The back of your TV may look similar to this:

From CNET: Connections - LG 32CS460 (pictures) - CNET Reviews

 

[markw]

Ya know, ...thinking about it...

Now that you said tis, iy puts a new slant on things.

Unfortunately Adam it does not have that ability, it's only composite in composite out.

That's a pretty primitive AVR* and most likely only DPL. Composite is pretty much the lowest common denominator in passing video signals, barely one step above the old RF modulated signals from primitive video games and first generation cable boxes.

If you have any video sources that use either component or HDMI, your best bet is to take your receiver totally out of the video path and feeding them directly to your TV and using that for video switching. If needed, get some sort of correct switching for those formats if you have more sources tan inputs.

Feed only your audio to your receiver and use that for audio switching. Bypass it for any and all video signals.

* that's not to say it's no good or useless. I have, and use, an old JBL JSR-400 like that and I use it in the bedroom, in stereo mode, in the exact same manner I describe here.