5++ in 1 Multi-Cable

If you are one of those people who never has the right cable when they need it then this project is for you. Turn one cat5 network cable into the Megatron of cabling by wiring custom adaptors and bridges. This straight through cable can transform into a crossover, serial, serial null-modem, cisco console, vga or vga extension cable by using four adapters, two links and one couple.

This project was originally published in vol 1 of Make (www.makezine.com) on page 96 and i highly reccomend reading it. Easy to follow wiring diagrams make it the perfect reference to read alongside this version. I've added a couple things you wont find in the mag such as vga over ethernet and alternate tecniques for creating the plugs.

Have fun and as always you can get me at [e-mail]

Step 1: Get Parts and Tools

MATERIALS
1 Length of Cat5 ethernet cable (complete cable)
1 Length of raw Cat5 cable
2 RJ45 to DB9 FEMALE (serial) converters
alternate: 2 RJ45 to DB9 male AND 2 DB9 female
2 RJ45 to HD15 MALE (monitor) converters
alternate: 2 RJ45 to DB9 male AND 2 HD15 male
1 RJ45 couple
4 RJ45 plugs
1 F-F HD15 gender changer (changes male to female)


TOOLS:
Soldering iron and supplies
RJ45 crimping tool
Wire cutters/strippers


NOTES:
If you have no use for a male to male vga cable you can replace one of the male HD15 connectors with a female and you wont need to buy the gender changer.

Step 2: Create the Mini-Crossover

To make a regular straight through ethernet cable into a crossover we will create a mini cable a couple inches long to flip the nessicary wires and add it to the regular cable with the couple. The first thing to do is strip the outer shielding and crimp on the RJ45 plug with the following connections:

SIDE 1
RJ45 Pin1: white-orange
RJ45 Pin2: orange
RJ45 Pin3: white-green
RJ45 Pin4: blue
RJ45 Pin5: white-blue
RJ45 Pin6: green
RJ45 Pin7: white-brown
RJ45 Pin8: brown

SIDE 2
RJ45 Pin1: white-green
RJ45 Pin2: green
RJ45 Pin3: white-orange
RJ45 Pin4: white-brown
RJ45 Pin5: brown
RJ45 Pin6: orange
RJ45 Pin7: blue
RJ45 Pin8: white-blue

The RJ45 pins are numbered from left to right if you are looking at the bottom (the side without the tab) of the connector with the tip pointing up.

Step 3: Make the Cisco Adapter

This cable is made the way as the crossover with this pin configuration:

SIDE 1
RJ45 Pin1: white-orange
RJ45 Pin2: orange
RJ45 Pin3: white-green
RJ45 Pin4: blue
RJ45 Pin5: white-blue
RJ45 Pin6: green
RJ45 Pin7: white-brown
RJ45 Pin8: brown

SIDE 2
RJ45 Pin1: white-brown
RJ45 Pin2: brown
RJ45 Pin3: white-green
RJ45 Pin4: green
RJ45 Pin5: orange
RJ45 Pin6: white-orange
RJ45 Pin7: white-blue
RJ45 Pin8: blue

Since it would be hard to tell this cable from the crossover it is nice to use another color cable, I did not have any other colors on hand so mine met Mr. Sharpe.

Step 4: Wire the DB9 Plugs

The two DB9 plugs that i found were male and we need female, so we have to convert them. The first thing to do is open the housing, there should be four clips that hold the two halves together. Once inside the case you can remove the guts of the plug and cut off the plug we wont be using. We can then solder these wires into the proper order:

RJ45 Pin1 (blue): DB9 Pin3
RJ45 Pin2 (orange): DB9 Pin5
RJ45 Pin3 (black): DB9 Pin2
RJ45 Pin4 (red): DB9 Pin7
RJ45 Pin5 (green): DB9 Pin4
RJ45 Pin6 (yellow): DB9 Pin5
RJ45 Pin7 (brown): DB9 Pin8
RJ45 Pin8 (white): DB9 Pin1 and DB9 Pin6

It is best to start by jumping pins 1 and 6 then finishing the top row of the DB9 connector. Once all the wires are connected put everything back in the housing and close it up. Repeat this process exactly for the second DB9 connector.

Step 5: Wire the HD15 Plugs

Open the RJ45 conversion housing and clip off the old connector. Strip the wires and solder them into the new connector according to the following chart:

RJ45 Pin1 (blue): HD15 Pin14
RJ45 Pin2 (orange): HD15 Pin13
RJ45 Pin3 (black): HD15 Pin3
RJ45 Pin4 (red): HD15 Pin7
RJ45 Pin5 (green): HD15 Pin2
RJ45 Pin6 (yellow): HD15 Pin5 HD15 Pin8 and HD15 Pin10
RJ45 Pin7 (brown): HD15 Pin1
RJ45 Pin8 (white): HD15 Pin6

Since pins on HD15 connectors are pretty cramped it is easiest to solder the middle row first then move to the two outside rows. Repeat this for the other HD connector and then your finished with construction!

Step 6: Use the Cable

Using the multi-cable isnt quite as daunting as it may initially seem here are the connections for the different configurations

Straight through ethernet:
Cat5 to Cat5

Crossover ethernet:
Cat5 to Cat5 - Couple - Crossover Mini-Cable

Serial cable:
DB9 - Cat5 to Cat5 - DB9

Null modem serial cable:
DB9 - Cat5 to Cat5 - Couple - Crossover Mini-Cable - DB9

Cisco console cable:
DB9 - Cat5 to Cat5 - Couple - Cisco Mini-Cable

VGA cable:
HD15 - Cat5 to Cat5 - HD15

VGA monitor cable
Gender changer - HD15 - Cat5 to Cat5 - HD15

Congratulations on your new cable creation! This general method can be used to emulate all types of interesting cables (that use eight or less conductors) so dont be limited to just the connectors in this how-to. Using google and a soldering iron you can make almost any cable you'll ever need!