Tim gregory Posted July 7, 2011 Share Posted July 7, 2011 I need to purchase some video baluns to run composite over Cat5 and the quality doesn't need to be that great. Do these passive baluns that are used for CCTV work OK?http://cpc.farnell.com/x-vision/xc5v/video-to-cat5-balun/dp/SR07293 My understanding of the way these work is that they just connect the screen and the signal to a twisted pair. Is there any difference to the way these baluns work?http://cpc.farnell.com/_/50-7730/cat-5-balun-av-phono/dp/AV17463 I presumed that as it is also passive it works the same and just sends left, right and video down a separate twisted pairs.This would not explain though why it needs to have a TX and RX (send and receive) surly if it is passive it would work the same both ways? Just trying to work this out so grateful for any answers. Tim Link to comment Share on other sites More sharing options...
bruce Posted July 7, 2011 Share Posted July 7, 2011 My understanding of the way these work is that they just connect the screen and the signal to a twisted pair.No - there's a balancing transformer inside. A bonus is that you get galvanic isolation.I presumed that as it is also passive it works the same and just sends left, right and video down a separate twisted pairs.This would not explain though why it needs to have a TX and RX (send and receive) surly if it is passive it would work the same both ways?There are transformers inside - different types for video and audio. So the video and audio circuits can't be interchanged, but they are bidirectional - the "tx" and "rx" are just labels. In fact, I just happen to have something similar sitting on my desk, and also have a conveniently located screwdriver... Link to comment Share on other sites More sharing options...
jason5d Posted July 7, 2011 Share Posted July 7, 2011 need low cost baluns?go for ebay - very cheap Link to comment Share on other sites More sharing options...
Tim gregory Posted July 11, 2011 Author Share Posted July 11, 2011 My understanding of the way these work is that they just connect the screen and the signal to a twisted pair.No - there's a balancing transformer inside. A bonus is that you get galvanic isolation.I presumed that as it is also passive it works the same and just sends left, right and video down a separate twisted pairs.This would not explain though why it needs to have a TX and RX (send and receive) surly if it is passive it would work the same both ways?There are transformers inside - different types for video and audio. So the video and audio circuits can't be interchanged, but they are bidirectional - the "tx" and "rx" are just labels. In fact, I just happen to have something similar sitting on my desk, and also have a conveniently located screwdriver... Thanks!! Wasn't expecting this level of service... That's great, will buy a couple and see how they look. Tim Link to comment Share on other sites More sharing options...
jacet Posted July 21, 2011 Share Posted July 21, 2011 Sorry for hi-jacking the thread but it's easier than starting a new one.I'm trying to get the LCD screens in our dressing rooms hooked up to our TV aerial so that the artists can watch freeview using the tuners built into them. Unfortunately I'm having difficulty getting coax to them so am looking into sending it over some spare (and already installed) cat5. My knowledge of the workings of tv transmission and RF is pretty poor so apologies in advance. Would I simply be able to get a pair of Baluns like this on each end of the cat5 to do the job or would that not work? Also, how would the analogue switch off (which starts in the next 2 months in this area) impact upon this set up? Cheers for any advicejacet Link to comment Share on other sites More sharing options...
timsabre Posted July 21, 2011 Share Posted July 21, 2011 Sorry for hi-jacking the thread but it's easier than starting a new one.I'm trying to get the LCD screens in our dressing rooms hooked up to our TV aerial so that the artists can watch freeview using the tuners built into them. Unfortunately I'm having difficulty getting coax to them so am looking into sending it over some spare (and already installed) cat5. My knowledge of the workings of tv transmission and RF is pretty poor so apologies in advance. Would I simply be able to get a pair of Baluns like this on each end of the cat5 to do the job or would that not work? Also, how would the analogue switch off (which starts in the next 2 months in this area) impact upon this set up?Cheers for any advicejacet No you can't send aerial signals with them. They are for sending composite video (the video signal after it's been decoded from the RF aerial signal)You could put a freeview set top box in a position where the aerial feed is easy, and send the video and audio from it over cat 5. They'll be stuck with the channel you choose though. Analogue switch off won't affect Freeview (although you'll probably need to do a retune the day they do it). Link to comment Share on other sites More sharing options...
Modge Posted July 21, 2011 Share Posted July 21, 2011 Also I take it the pre-installed cat-5 is just a cable to which you have access to both ends of? Or at least can be re-patched? Connecting this to any sort of switch will end in tears... Link to comment Share on other sites More sharing options...
henny Posted July 21, 2011 Share Posted July 21, 2011 Yes you can send rf over those See http://www.hypex.co.uk/files/pdf/16531/lynx-video-network.pdf Distributes up to 96 RF channels (5-860Mhz)Cat 5 or Cat 6 cableDistributes digital and analog TVCATV and MATV SystemsSimplifies cabling requirementsIncreases flexibility for moves, adds and changesImproves reliabilityCreates a bridge to IPTVThe Lynx Video Network simultaneously delivers up to 96 RF channels on Cat 5e or Cat 6 cable. It is ideal for distributing channels from CATV, satellite, off-air, DVD,or video camera sources. Frequency capabilities are 5MHz to 860 MHz.A Lynx hub in the wiring closet converts an unbalanced coaxial signal into eight or sixteen balanced signals transmitted on twisted pair cables. At the point of use a wallplate F or single port converter (040-0074) is required to change the signal back to coaxial form. Link to comment Share on other sites More sharing options...
jacet Posted July 21, 2011 Share Posted July 21, 2011 No you can't send aerial signals with them. They are for sending composite video (the video signal after it's been decoded from the RF aerial signal)Sorry, I didn't make that very clear, the ones I linked to were RF ones as opposed to composite ones. We've used some of the composite ones (with the ir repeater) in the past with a separate freeview box but are looking to give them a more convenient solution. Also I take it the pre-installed cat-5 is just a cable to which you have access to both ends of? Or at least can be re-patched? Connecting this to any sort of switch will end in tears...Yes they're just direct cat5 runs of approximately 25m, they don't even pass through a patch panel which will stop 'helpful' others from accidentally unplugging them. Yes you can send rf over those See http://www.hypex.co.uk/files/pdf/16531/lynx-video-network.pdf Distributes up to 96 RF channels (5-860Mhz)Cat 5 or Cat 6 cableDistributes digital and analog TVCATV and MATV SystemsSimplifies cabling requirementsIncreases flexibility for moves, adds and changesImproves reliabilityCreates a bridge to IPTVThe Lynx Video Network simultaneously delivers up to 96 RF channels on Cat 5e or Cat 6 cable. It is ideal for distributing channels from CATV, satellite, off-air, DVD,or video camera sources. Frequency capabilities are 5MHz to 860 MHz.A Lynx hub in the wiring closet converts an unbalanced coaxial signal into eight or sixteen balanced signals transmitted on twisted pair cables. At the point of use a wallplate F or single port converter (040-0074) is required to change the signal back to coaxial form.Cheers for the clarification henny, I had read that sheet but I was unsure of what the frequency range meant with regards to using it for this application (as I said, I'm an RF novice). Cheers for the inputjacet Link to comment Share on other sites More sharing options...
bruce Posted July 21, 2011 Share Posted July 21, 2011 Sorry, I didn't make that very clear, the ones I linked to were RF ones as opposed to composite ones. We've used some of the composite ones (with the ir repeater) in the past with a separate freeview box but are looking to give them a more convenient solution. Hmmm - never seen those RF variants before. I guess they may well do the job. But at 100 quid a time, for a solution that is untested, (50 pound per device, need one each end) I'd be thinking about pulling in some coax... Link to comment Share on other sites More sharing options...
jacet Posted July 22, 2011 Share Posted July 22, 2011 Hmmm - never seen those RF variants before. I guess they may well do the job. But at 100 quid a time, for a solution that is untested, (50 pound per device, need one each end) I'd be thinking about pulling in some coax...Indeed, I was hoping someone on the BR might have had experience with them and could let me know if they were able to carry a strong enough signal to the other end.I'm still trying to work on a coax solution, but the logistics of it is proving a nightmare. Link to comment Share on other sites More sharing options...
ramdram Posted July 23, 2011 Share Posted July 23, 2011 I don't believe it. Artistes...watching Freeview...in their dressing rooms? Whatever next? Free teabags and Fairtrade recycled coffee, deary, deary, deary me. Did this requirement turn up in a rider perchance? The only screen our lot get to watch is the stage relay. Link to comment Share on other sites More sharing options...
henny Posted July 23, 2011 Share Posted July 23, 2011 Cheeper option would be to go out and buy an active in-door tv arial and try It out in each room, where it works problem solved/money saved Link to comment Share on other sites More sharing options...
timd Posted July 23, 2011 Share Posted July 23, 2011 Pull some coax through using the cat5? Or better still, pull a pull cord through using the cat5, and then use that to pull the coax and cat5 back in. Link to comment Share on other sites More sharing options...
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