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Cisco DCE Adapter for P25 STUN Connection to Quantar

In order to connect a Motorola Quantar to a P25Reflector for P25 operation I had to setup a new system for testing purposes. To connect the Quantar to a Cisco router for STUN encapsulation one normally used a Cisco V.24 DCE cable with an adapter to RJ45 on the Wireline card of the Quantar ([1]).

During placing an order with Mouser Electronics I identified the 60pin LFH connector manufactured by Molex by random. The idea was born to directly homebrew a nice cable to connect the RJ45 plug on the wireline board to the Cisco router.

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While discussing on a P25 group Tobias OE9TEV added the idea to use an SubD15 to RJ45 case for that so that a common LAN cable could be fitted in between. So I disassembled a Cisco cable and measured all pins on the V.24 DCE cable.

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The pinout is shown in the picture above (Sorry, no KiCad drawing due to missing footprint of the Molex LFH connector). I used part number 636-RJADK15P7080821 as case ([2]). The colors apply to this case. YMMV. Some pics of the inner details at [3].

References

[1] https://www.qsl.net/kb9mwr/projects/dv/apco25/IP%20link%20Quantar%20V.24%20systems%20using%20Cisco%20routers%20V2.pdf
[2] https://www.mouser.de/ProductDetail/636-RJADK15P7080821
[3] https://twitter.com/flo_0_/status/1161284478423228417?s=20