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Modular Phone Jack Pin Out for RS232 Connector

I am new to this forum and hope someone may be able to help.

I am unable to connect my iPad to my AstroPhysics GTO mount using SkyFi-USB wireless serial and USB adapter. I am connecting the device to my mount using a RS232 wire purchased from simulation curriculum at the same time as the device. I have always been able to connect to my iPad running SkySafari+ in the past - the last time was Saturday, May 12. Last night I was unable to make a successful connection. Today I tried to connect to my AstroPhysics Mach1GTO. Still unable to connect successfully. I suspect the phone jack connector that plugs into the SkyFi device. What I need is the pin out colour code for the phone jack connector. There are 9 colour coded wires coming from the RS232 end, but not all are used in the modular phone jack connector which has 6 pins. With the modular phone jack pins UP and the opening where the wires would enter the jack, the wire colour from right to left would be ...? It appears that not all six pins are used in the phone jack, although it is difficult to tell. I can clearly see that red,yellow and possible brown are used.  Can anyone please provide the wire colour to pin-out for the phone jack?

My apologies if this question has been asked before.

Brett Hardy

1 comment

  • 0
    Bill Tschumy

    Just to be clear, you are using the older "rectangular" SkyFi that takes 4 AA batteries, right?

    We do have information on building serial cables here:

    However, we also say that we cannot provide support for building your own cable.  It is hard to troubleshoot.

    We don't sell the serial cable for the AstroPhysics mounts.  If you bought a cable from us then it would only work if the AStroPhysics pinouts happen to match your cable.

    It sounds like you are saying this cable used to work for you but now it doesn't, right?  It could be the SkyFi serial port.  It could be the cable. It could be the mount.  Determining where the failure is generally involves trying other pieces of equipment to find out which is bad.

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