RS232 Signal Splitter


Thread Starter

Alvin C. Cipriano

I am presently searching for a Supplier or Manufacturer of a RS232 Signal Splitter, Does anyone could help me find one please....... What are the available RS232 Signal splitter in the market today and how do they differ from each other if any?.......

Scott Whitlock

I once tried finding a similar device without any luck. The RS232 ports are usually meant for point to point communications... but I did
find a way for a third party to eavesdrop on an RS232 connection:

1) Start with a normal RS232 straight through cable.
2) Connect Pin 5 of the third (eavesdropper) connector to Pin 5 of the cable.
3) Connect Pin 2 of the eavesdropper connector to pin 2 of the cable *using a 2.2k resistor*.
4) Connect Pin 2 of the eavesdropper connector to pin 3 of the cable *using a diode* (1N4148 will work). The eavesdropper gets negative end
of the diode, and the cable pin 3 gets positive end.

Hope this might help.

Mike Winburn

What exactly are you splitting?? Could you use a 232/485 converter and go multidrop?? Black Box makes a databroadcaster which is simply a 1-in, 8-out box. We use them on some PLC applications when we have needs for multiple 232 connections with a single port. Black Box P/N TL160A-R2 for buffered or TL158A-R3 non buffered.
I need the RS232 COM Spliter too but I didn't understood what you meant, please if you can contact me I'll be gladfull.

Thank you.
Jozsef (jozsef
<p>You can make one very simply. No diodes or resistors necessary but the device that is going on this pigtail lead must not need the DTR or DSR signal or any other signals other than Ground and Receive Data. It was mainly developed for use in a point of sale device for a text to video capturing device to capture what is printed on the serial receipt printer.
DB25M DB25F DB9M Pigtail
Pin 3 Pin 3 Pin 2
Pin 7 Pin 7 Pin 5
All other used pins go straight through from DB25M to DB25F.
<p>This Y cable will not allow for the extra serial device to transmit on this cable. RS232 was not designed to connect more than one serial periferal device at a time but you can monitor the trafic on the rs232 wire with just these 2 connections. Pin 7 on the DB25 is the ground signal. The Pin 3 I think is the transmited data from the computer or Point Of Sale device in my case. This all depends on the need for the various DTR and DSR signal needs. My text to video capture device does not need them so it works just fine.

<p>I'm just looking for the parts now. The splitter I have or Y cable as it is called in some circles uses a DB25M to DB25F straight through connector with a circuit board between the connectors with solder points on each trace. The pigtail has 2 wires soldered to the traces.