E1-to-RJ45 » History » Revision 8
Revision 7 (Anonymous, 02/19/2016 10:47 PM) → Revision 8/14 (dexter, 02/19/2016 10:47 PM)
== Howto build your E1<>RJ45 cable ==
We used a Cat-7 Ethernet cable to build our E1<>RJ45 cable to connect the BTS with the BSC.
Things you need:
* one Cat-7 Ethernet cable
* two twinax plugs (BR2)
* some heat shrink tube
* soldering-iron
* multimeter (optional)
* a sharp knife :)
=== Step-by-step guide ===
'''One:'''
Take your cable and cut off one of the RJ45 connectors. Now use a ruler and make a slice so you can strip around 15 cm from your cable.
[[Image(IMG_0960-1.JPG, 15%)]] [[Image(IMG_0960-2.JPG, 15%)]]
'''Two:'''
Split the wires from your cable. We need pin 1 and 2 for '''RX''' (green white/green) and pin 4 and 5 for '''TX''' (blue white/blue), you can use a multimeter if you are not sure you got the correct wires. Cut off the other wires we do not need them (yet).
[[Image(IMG_0960-4.JPG, 15%)]] [[Image(IMG_0960-5.JPG, 15%)]] [[Image(IMG_0960-7.JPG, 15%)]]
'''Three:'''
Sort your twinax plugs to make sure you build them in the right order. ;)[[BR]]
We used heat shrink tube to stabilize our cable around the plugs.
[[Image(IMG_0960-9.JPG, 15%)]] [[Image(IMG_0960-11.JPG, 15%)]]
[[Image(IMG_0960-12.JPG, 15%)]] [[Image(IMG_0960-17.JPG, 15%)]]
'''Four:'''
Now you can put everything on the first part of the cable and assemble it. Use a soldering-iron to fixate each of the two pins of the plug with your wires. You do not have to worry about the polarity inside the twinax plug.
[[Image(IMG_0960-19.JPG, 15%)]]
'''Five:'''
Repeat step '''three''' and '''four''' to build the second plug.
'''Done.'''
[[Image(IMG_6379-1.JPG, 15%)]]
== Detailed pinout ==
{{{
Signals on the RJ45 plug:
____________________
/ / / |
/ / / /|
/ /_______________/ / |
/ ________________ / |
/ / / / / / / / / / / |
/ / / / / / / / / / / /
/ /_/_/_/_/_/_/_/_/ / /
| | | | | | | | | | | /
| |8|7|6|5|4|3|2|1| | /
| |_|_|_|_|_|_|_|_| |/
|___________________|
| |/
\______/
1 = RX1
2 = RX2
3 = NC
4 = TX1
5 = TX2
6 = NC
7 = NC
8 = NC
Signals on the twinax plugs:
E1 Transmitter:
___
.-'' '`-.
.' `.
/ 1 2 \
: ## ## ;
| ## ## |
: ;
\ ############# /
`. ######### .'
`-._____.-'
1 = TX1
2 = TX2
E1 Receiver:
___
.-'' '`-.
.' `.
/ 1 2 \
: ## ## ;
| ## ## |
: ;
\ ############# /
`. ######### .'
`-._____.-'
1 = RX1
2 = RX2
Note: The drawings are showing the plugs point of view.
Note: This is a differential connection with symetric signals
so you do not have to care about the polarity.
Cable connection on the BS11:
~~~~~~~_________~~~~~~
/ oo oo \
\ 12 /
~~~~~~~|_______|~~~~~~
1 = RX (E1 Transmitter to that port)
2 = TX (E1 Receiver to that port)
}}}