How to solder a null modem cable RS-232

They asked me to flash a satellite tuner somehow, started looking for a cable, but it isn’t there, but there was a bunch of ordinary RS232 (mother-to-father). I had to think about how to solder homemade.

What you need: 2 connectors – RS-232 mom (which has holes for the contacts inside), you can cut it off from ordinary cables or buy (or it’s easier to buy a finished cable).
A piece of twisted pair cable that is commonly used to connect the Internet to a computer or router, etc.

I will give an example of a standard soldering of a null modem cable (we solder the legs and the case as indicated):
1 connector 2 connector
1 + 6 <-> 4
4 <-> 1 + 6
3 <-> 2
2 <-> 3
5 <-> 5
7 <-> 8
8 <-> 7
housing housing

Although, in fact, for the firmware of the tuner, basically just soldering:
1 connector 2 connector
2 <-> 3 (RxD)
3 <-> 2 (TxD)
5 <-> 5 (GND)

By the way, in a regular RS232 modem cable (dad mom), the legs are soldered the same way, that is, 1-1, 2-2, 3-3, etc.

Done.

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