Crossing Over

Part 4 of Don’t Do It Yourself DSL

The following instructions were written in 2000 when DSL was a relatively new thing! We’re keeping it up for posterity. It’s old information but may be helpful to someone somewhere.

Up until this point the Tip and Ring have been consistent and kept in “straight through” fashion. However, the RJ11 cable that runs from the wall to the phone or the modem has the pairs reversed on one end. Now, in Ethernet Land, this is what we would call a crossover cable. In Telephone Land, it is just a regular cable. I suspect that every RJ11 phone cable in your house looks like this. To a certain extent this makes sense when you look at the RJ11 pinout on the DSL modem jack. On the other hand, with RJ45 10/100BASE-T Ethernet cables (which is what you will use to connect your CPU to the DSL modem) there are always two active pairs. One pair is a Transmit, one is a Receive, each pair has a one (+) side and one (–) side. In the picture at the right, the first pair is the Orange pair made up of one solid Orange conductor and another Orange conductor with a White stripe. The other pair is the Green with the same pair/color configuration. Notice how the Green pair skips over the center two Blue conductors. Ethernet NEVER uses the middle pair because that is what the phone company uses as their primary phone pair and if you somehow managed to get a 90 VAC ringer signal into your Ethernet card you would be very, very sad. If the Ethernet cable in the picture was a crossover cable the Orange and Green pair would exchange places on one end – similar to the RJ11. RJ45 Ethernet crossover cables are generally used when you connecting devices of like kinds: CPU to CPU, hub to hub. In this case of DSL we are going from a Westell Brand Modem, Model: Westel WireSpeed Ethernet ADSL Modem, Model Number: B90-36R516 to CPU, so a “straight through” cable is what we use.

RJ45 straight through cable ends. Same order on both ends.
RJ45 straight through cable ends. Same order on both ends.
RJ11 cable ends. Pairs Reversed?!
RJ11 cable ends. Pairs Reversed?!
RJ11 Pinouts
RJ11 Pinouts

It’s just so handy dandy!

Now that the wall jack is wired and the POTS splitter is wired, you can, once again, plug your handy dandy modular telephone line tester into the DSL line to check it. Even though it’s DSL, it will still give you a signal as to whether or not your Ring and Tip are reversed. At this point, you are ready to start the computer/modem hook up. With the PacBell DSL kit I received a Kingston 10/100BASE-T Ethernet card. By the way, the jack on 10/100BASE-T Ethernet cards is RJ45. The card seems decent and came with both Windows and Macintosh drivers. Since I own a Power Macintosh G4, 10/100BASE-T is standard. No card to install for me. For older Macs and Windows machines, you may need to install the Ethernet card. Sorry, but all I can say on this is to read the directions that came with the card, ground yourself, open your case, find an open PCI slot, install the card, install the drivers and cross your fingers. Remember, SmellyEyeball is NOT responsible for little tiny dropped screws, cracked PCI slots, cracked Ethernet cards, cracked motherboards, little tiny cuts you receive from those sharp case edges or any other damage you do to yourself, your equipment, your family, your pets, your neighbors, your local police and fire officials, liquor store clerks or CompUSA trained service technicians.

By the way, I squished the telephone line tester picture on purpose to save space.

The handy dandy modular telephone line
tester green lighting the DSL
The handy dandy modular telephone line 
tester 
green lighting the DSL

Plug it in! Plug it in!

Now that we have the wall jack wired, the POTS Splitter wired and your Ethernet card installed we can finally plug everything in. With all power off on the modem and CPU, in no particular order: Plug the power cable into the modem, the other end into a handy electrical outlet (surge protector preferred) Plug one end of the RJ11 cable into the wall (DSL jack) and the other end into the RJ11 jack on the modem. The Westell’s RJ11 jack is marked LINE. Plug the Ethernet cable into the RJ45 jack on the back of the modem and the other end into the Ethernet card in the CPU. The Westell’s Ethernet Jack is marked ETHERNET. With everything plugged in you now can fire everything up! The CPU, the DSL modem, the rock tumbler, and the TV.

What happens next depends on how far along you are with your ISP. Your DSL may already be active, or it may not. The DSL signal may be active but your ISP may not have put your info into their routers yet. Hooking up your own equipment at your house is just the first part of the whole DSL experience. The other part depends heavily on your ISP, which in my case is PacBell.

RJ45 on CPU
RJ45 on CPU
Westell Modem back connectors from left to right: RJ11 (goes to wall jack), power cable,
RJ45 (goes to CPU/Ethernet card).
Westell Modem back connectors from left to right: RJ11 (goes to wall jack), power cable,
RJ45 (goes to CPU/Ethernet card).

Lights, Ready, DSL!

There are 4 lights on the Westell modem, I suspect that this is the case on most DSL modems. Starting from the top: Power, Ready, Link, and Activity. When everything is plugged in and turned on the Power Light on the modem should be on. The Ready Light won’t necessarily be on but if your DSL signal is hot then it will start flashing and eventually go to a solid green, indicating that you have synced. After you install to configure your TCP/IP software (drivers to recognize the DSL modem and signal) you can try to connect. Once again, you are on your own here. The software differs greatly from Mac to Windows and the best advice is to read ALL the directions that came with the software and follow them step by step. If everything is a go on their end and you connect, the Link light will go solid green and you will get little flashes on the Activity light. However, most likely the next thing you will be doing is waiting on hold with your ISP’s tech support wondering why you cannot connect. Speaking from my experience, PacBell did not have me in their routers so I had to wait a while. That is a story for my next installment in this saga. Hopefully, I will get to that someday soon, although the information there will be mostly anecdotal and will not offer much in the way of needed information.

Westell Modem showing all green lights
All hooked up!

Comments?

If you have any comments about this page including criticism or corrections that I need to make, please let me know. This is the first page of this sort I have written and I would like to hear what people think. I am sure there are plenty of typos and technical errors, but as I find them I will do my best to correct them. May the Install Gods be with you.