Hi ShadyBro, yes you see it right, although the ST555 filter becomes part of the ST2206 (although purchased seperately) but electrically your diagram is correct.
And yes the idea is all the room TO's (Telecom outlet aka RJ45 socket) come back and terminate on the patch panel, from there using patch cords you can either patch ethernet from the switch to a particular TO or phone from the ST2206 patch ports to any particular TO.
Butj, its transmission line theory that directly answers your question, for voice it does not matter, but once over roughly 100kHz the line looks like a 100ohm transmission line. The impedance of the line is dictated by the diameter of the two conductors and the distance apart they are, and the dielectric characteristics of the insulation between the conductors. If you separate the conductors then the impedance will rise and will result in reflections that will degrade signal performance. By twisting the wires together we form a mechanical structure that helps keep (or tie) the two wires of the pair together and helps maintain a constant distance apart.
Obviously twisting the wires also helps with common mode interference rejection, but short lengths of untwist will not significantly effect that aspect, its the line impedance that we are trying to maintain by maintaining twist as long as possible.
As I say untwist will have little ill effect on voice (will if you say untwisted 50-100mm or so) but for DSL and ethernet which are radio frequencies then line impedance is important.
Excellent, thanks for the reply Cyril, are you still selling the ST2206 units or will I have to go through an electrical wholesaler as I see Signal only supply directly to the wholesalers.
Hi, the ST2206 is a Signet product, I just designed it for them after I approached them with my original product and we both decided to go down the course of this format. I think you will find they are slightly cheaper than I could supply the original as they are built in large numbers in Asia, compared to me hand building each one :)
I can supply one for you if you think your wholesaler is not giving you a reasonable price, PM me with what they quote and I will see what I can do.
Thanks Cyril for the theory, I figured something like that. I guess when I'm trying to punch down the 8 wires on a connector, i'm wondering how close to the 5mm I have to be. On the keystones its a bugger to get the whole cable into the plug connector and at the same time meet the 5mm rule. I guess there a trick to it and that's why I don't do it for a living! Thanks again. Great product. I've shown my sparky and he's impressed.
Hi depending on what connectors I am using its normal to achieve no untwist and the sheath remain in place right to the first approach to the IDC header, so the sheath remains right to the IDC header or within 2-3mm of it, this is an ideal and takes some practice. There should be no need to do any untwist, as the IDC header will have a divider to split the pairs, simply splay the pair over the divider without untwisting. If you need to untwist to get the pair polarity aligned then try adding twist rather than untwisting. With cat5e I normally always add twist to the tan pair as that pair is normally the least twisted and often drops apart once unsheathed.
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