After the PK-232, I wanted a PK-900 but AEA PK-900 is a rare sight. I found one on E-Bay with only 6 mins left to go. I promptly bid and won so now have one of the best TNC devices made. The connection cable below is for the HF Data port on the FT-847 to the PK-900 using the same cables as for the other PK-232 cables on this site.
There are a few issues to be aware of. In the case of using the Data port in the FT-847, there is a hang time on the PTT that is too long for Packet QSO's to be viable. I posted a message in the Packet Radio Forum that I belong to and another user of the FT-847 had the same issues and resorted to the Front Mic Connector, and rear Ext Speaker for the connection. That started to look a bit of a cable nightmare when dealing with all the other cables I have here. I had a bit of a google around and fell upon a note in a SuperControl.de page about long changeover on the FT-847 and there was another way.
The note said that some people had good results with using a 100nF (0.1uF) capacitor or 200nF (0.2 uF), so I set about trimming off all the nice neat heat shrink that I'd put on when making the cable up. Replacement of the capacitor for a 100nF has speeded up the transfer to one that will now support AX-25 Packet.
Anyway, I learned so you don't have to. You can either build the cable as I have below or experiment with a different capacitor value. There are also notes elsewhere that say to up the resistor to a 2.7k Ohm one but there is little explanation of why.
REAN Stereo NYS231BG-LL Extra large entry 3.5mm Mini Jack plug
JY-8022 Twin Audio Shielded Cable
2k Ohm 1/4 watt Resistor
10 uF Electrolytic Capacitor - SEE ABOVE NOTE FIRST
5 pin DIN Connector