Component Video & Stereo Audio over one Cat5e - AVS Forum
Forum Jump: 
 
Thread Tools
post #1 of 9 Old 08-20-2011, 11:28 AM - Thread Starter
Newbie
 
nathan909's Avatar
 
Join Date: Jul 2009
Posts: 4
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
I have a bunch of these baluns laying around
http://www.ebay.com/itm/20x-Camera-C...item4aab6e69b6
about a $1 each shipped

I send video over it no problem, but I have a few questions:

1. Can I send Audio over cat5 without a balun?
2. Can I send Audio over cat5 with the same video balun on a different pair?
3. How can I send Component & Stereo audio over one cat5 like seen here:
http://www.ebay.com/itm/COMPONENT-VI...item2a11accc31
(sharing grounds and using the extra pare?!)


Thanks for any info,
Nathan
LL
nathan909 is offline  
Sponsored Links
Advertisement
 
post #2 of 9 Old 08-21-2011, 12:23 AM
AVS Special Member
 
Colm's Avatar
 
Join Date: Aug 2002
Posts: 4,652
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 87
Quote:
Originally Posted by nathan909 View Post

1. Can I send Audio over cat5 without a balun?

Sure, but you won't like results. You will have problems with noise and attenuation of the signal
Quote:


2. Can I send Audio over cat5 with the same video balun on a different pair?

Should work OK. Try it.
Quote:


3. How can I send Component & Stereo audio over one cat5...?

With a device like the one you linked to.

FWIW you don't have a ground in the same sense you would with a single-ended circuit, so you cannot connect the wires.
Colm is offline  
post #3 of 9 Old 08-21-2011, 08:44 AM
AVS Special Member
 
crutschow's Avatar
 
Join Date: Feb 2008
Location: USA
Posts: 1,774
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
A video balun likely won't have the low frequency response needed for good audio but you can try it, as Colm suggested.

Carl
Curmudgeon Elektroniker
crutschow is offline  
post #4 of 9 Old 08-21-2011, 09:01 AM
AVS Special Member
 
SAM64's Avatar
 
Join Date: Apr 2011
Posts: 1,567
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 7 Post(s)
Liked: 69
Quote:
A video balun likely won't have the low frequency response needed for good audio but you can try it, as Colm suggested.

Why? Baseband video starts at DC.

I also doubt that those baluns actually contain a transformer.
SAM64 is offline  
post #5 of 9 Old 08-21-2011, 11:56 AM
AVS Special Member
 
crutschow's Avatar
 
Join Date: Feb 2008
Location: USA
Posts: 1,774
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by SAM64 View Post

Why? Baseband video starts at DC.

I also doubt that those baluns actually contain a transformer.

It may theoretically go to DC but there are few low frequency components in a normal video signal spectrum below the 15kHz (or higher for HD) line rate. DC restoration is normally used to clamp the sync negative peak and establish the DC level.

To go from single-ended to differential and back, as a balun does (by definition) requires a transformer.

Carl
Curmudgeon Elektroniker
crutschow is offline  
post #6 of 9 Old 08-21-2011, 12:23 PM
AVS Special Member
 
olyteddy's Avatar
 
Join Date: Oct 2005
Posts: 3,186
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 38 Post(s)
Liked: 195
Quote:
Originally Posted by SAM64 View Post

Why? Baseband video starts at DC.

I also doubt that those baluns actually contain a transformer.

I wouldn't buy a passive balun that wasn't a transformer. I did some building at public access TV stations and I used dual op-amps to build differential drivers when I needed a balanced audio line. I agree though that transformers that small aren't too likely to pass good bass.
olyteddy is online now  
post #7 of 9 Old 08-22-2011, 08:33 AM
AVS Special Member
 
SAM64's Avatar
 
Join Date: Apr 2011
Posts: 1,567
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 7 Post(s)
Liked: 69
Quote:
It many theoretically go to DC but there are few low frequency components in a normal video signal spectrum below the 15kHz

H Sync is at 60Hz, quite a bit lower than 15.734 KHz.

Quote:
To go from single-ended to differential and back, as a balun does (by definition) requires a transformer.

Correct.
How many quality baluns have you seen with a flat 5MHz frequency response, that retail for $1.00?
SAM64 is offline  
post #8 of 9 Old 08-22-2011, 11:04 PM
AVS Special Member
 
crutschow's Avatar
 
Join Date: Feb 2008
Location: USA
Posts: 1,774
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Quote:
Originally Posted by SAM64 View Post

H Sync is at 60Hz, quite a bit lower than 15.734 KHz.

It's true the V (not H) Sync occurs at 60Hz but the V sync signal actually consists of a group of inverted sync pulses occurring at a 31.4 KHz (twice horizontal) rate so there is little actual 60Hz fundamental component in the video.

Carl
Curmudgeon Elektroniker
crutschow is offline  
post #9 of 9 Old 08-28-2011, 09:55 PM
Newbie
 
GoClippers1969's Avatar
 
Join Date: Aug 2011
Posts: 4
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Some of this depends on how well they have twisted the pairs in the Cat5. All pairs should be twisted at different frequencies which limit the amount of cross talk and noise that can occur. It also depends on how long you want to run this and if you are using 350 Mhz wire or 100 Mhz CCA.
GoClippers1969 is offline  
Reply Home A/V Distribution

User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off