[shiggins]

Well, not strictly Head-Fi related but definitely DIY. My folks have just got an LCD telly and want to connect their DVD player via component cables (well, I want them to). These need to be quite long and routed under the carpet around some corners so need to be reasonably thin. Prices for decent and/or longer component cables are surprising to say the least and mostly fat. So, I'm gonna make some for them; afterall it's only some 75ohm coax with RCA's on the ends. Rapid do a coax cable that looks reasonable and only 4.5mm across - I'll forego all the techflex and bling to keep diameter down. Thought I might as well do it properly and get the closest to 75ohm connectors that I can. Changing connectors to BNC is not an option - warranties and all that. I know that Canare do 75 ohm (they claim) RCA's but I cannot find a source for them in the UK. I did find them Canford I think but their site is so confusing I don't know what to order.

So, does anybody know where I can get Canare or any other make of 75 ohm RCA connectors in the UK? Are these actually any better than bog-standard connector?

Thanks in advance.

 

[Pars]

Check enjoythemusic.com for the "Max Rochlin Memorial Cable", which is a component video cable made using Belden 1506A (IIRC) and Canare RCAs. The RCAs are confusing, because they have different versions of them depending upon which cable you are using them withl. You also have to order the center pins and the crimp ferrules seperatly, again depending upon cable type (at least for the center pins).

That being said, how much better (and closer) to 75 ohms these are is not quite clear. They are nice connectors and reasonably priced, once you get past the technical hurdle of determining what you need. Check also some US suppliers (Pacific Radio at www.pacrad.com or Marketek) for perhaps some clearer information... once you have figured out the Canare PNs you need you should be able to figure out what to order from Canford. Also, they make some color coded silicone boots for these that just happen to be available in Red, Green and Blue, perfect for component video cables. I think Canford had them under the second Canare RCA category... minimum is 20pcs.

hth

Chris

 

[1UP]

From what I understand, most RCAs are not truly 75ohm! Plus it's wasted unless you can guarantee compliance at every point along the signal path - source output connector, cable terminators, input device connector.

Otherwise, WBT claim their Nextgens can do it. Also try markgrantcables.co.uk - he has access to canare and belden pieces and can make custom cables. I believe the canares can only be 75ohm if you use their expensive crimping method/tool, which costs £££.

 

[shiggins]

Thanks Pars, for the more English descriptions and the link to enjoythemusic.com. Are you sure pins/ferrules do not come with the connectors? Otherwise, they're 100 pcs minimum and another £60 from Canford. The Canare site was no use for connector type to cable width - Just lists cable types for use with each connector. I'll have to look into the listed cables to see if any are similar widths to the slim coax cable I've picked out. I'll get round to that tonight.

1UP - Yup, from what I gather most RCAs are no where near 75ohm, hence why I'm looking for these Canare RCAP connectors (which are at least close to 75ohm). I wouldn't say this was a waste. I may not be able to ensure the plugs on the dvd player & tv are 75ohm (pretty sure they're not) but I can at least make sure the cable is. Cable crimps are relatively inexpensive, besides I crimp all my TV aerial leads with pliers! WBT Nextgens are too pricey. And markgrantcables.co.uk - there's no way my folks would spend >£100 on a cable. They'll probably end up with generic RCAs anyway now, just like most other component cables.

 

[Pars]

Oh yeah, I just crimped mine with pliers (the ferrule). The pin just crimp with needlenose pliers and solder. I thought the impedence was determined by the conductor geometry (i.e., how far the center pin is from the shell, etc.) I wouldn't think that the crimp method would have any effect whatsoever on this. Of course, I could be wrong...

 

[DaKi][er]

Common RCA's are around 30 ohms as quoted by jocko homo off diyaudio.com

Any other RCA that claim to be 75 ohms really are NOT so, unless you replace the jacks with their special ones to match as well, the jack is just as important here as the plug itself and unless you have both you are wasting your time!

Seeing you have to replace the jacks to get true 75 ohms why would you pay top $$ for fancy rca ones when any 75 ohm BNC will do here?

Same goes for digital audio

So i see it as you have 2 choices, use any old rca and live with the fact you dont have 75 ohms or replace them all with BNC's

 

[shiggins]

Well, yesterday I made three 10m runs with crappy RCA's on the ends, set up the TV and DVD player for progressive component signal and watched Sin City. The picture is stunning! £30 well spent. Looks like I'll be going round my folks place to watch films more often now. Dammit, don't you hate it when your parents have better technology than you.

Must...resist...new...telly.

 

[Garbz]

Yeah well it's not because of the plugs. The only way to increase the impednace of the coax type RCA plugs is to reduce the mass surrounding the center pin. This works in theory untill you plug it in as Daki][er has pointed out. Once the plugs are in the mass around the centre pin is a function of the mass of the plug and the mass of the socket, and bam you're back to 25-30ohm.