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FT-1K OptoCAT - The simple and safe RS232 CAT interface for Yaesu FT-1000MP, FT-1000MP Mark V and FT-1000MP Mark V Field rigs
After having designed and built the interface for my Kenwood TS850S (see SSK232), it was needed to design and build (quickly...) a safe interface for our brand new Yaesu FT1000MP Mark V. This radio has a standard RS232C CAT interface and it is ready to be connected with a PC but, as usual, I don't like to connect the radio to a PC directly, without electrical separation, especially when is to be used in "rude" RF environment like in a contest station.
The interface is similar to the one for the TS850S, but, in this case, I choose two single, easy to find, optocouplers model 4N25. I take the power for the radio side from the 13.8V connector of the FT1000, because there are no control signals to use on the CAT DB9 connector (only TXD, RXD and GND are connected).
To power the circuit on
the PC side, I use
the DTR and RTS signals of the PC: with all the software I tested, these pins
are at +12V .
I built it using the ugly construction on a little un-etched piece of copper-clad circuit board that fit in a very little plastic box.
you want, you can use one double optocoupler TLP504A or CNY74-2.
With 200W, my interface
doesn’t need any filter (capacitor and/or inductor), let me know if you have
RFI problems and I will suggest some filtering.
The interface is tested
and perfectly working at 4800 baud with CT9, Writelog and Easylog; I think that it will work
with any software that don't needs the handshake to the radio with RTS and CTS.
My "radio" PC is a P200MMX on an ASUS TX97E motherboard but the interface worked fine also connected to the "main" PC, a PIII 933MHz (Intel 815 chipset) and a P133 Notebook using two 2m long shielded serial cables.
Ciao and good work
Guido, ik2bcp / iu2r / ab9dg
You can download this schematic with better quality as PDF file: Yaesu OptoCAT by IK2BCP.pdf
Any question and/or comment to ik2bcp AT hamlan.org