I watched a clip on an episode of Ham Nation detailing making use of the ACC socket on the back of an Icom rig and this prompted me to make a simple lead to take the audio feed out via the socket to one of my shack speakers.
Included in the box of the IC-7100 was a little bag containing a few spares and accessories, one of which was a pre wired ACC connector. All I had to do was to figure out what two wires I needed, and which ones I could cut off. I found that information in the user manual, the light blue wire is the AF Detector output whilst the red wire was the ground.
To make the lead I cut off a 3.5mm jack on an existing 3.5mm jack to RCA audio lead that I had, I then stripped the wires back, twisted the grounds together and then the AF signal wires together. A quick solder permanently fixed the wires, and a bit of heat shrink covered everything up nicely without shorting together.
A quick test with the DMM confirmed there were no shorts, so I went ahead and connected the lead to the ACC socket on the rig, and the RCA plugs to the speaker.
Once the rig was powered up audio could be heard through the speaker, a bit too much so I instinctively turned the AF knob on the rig down, however this had no affect, due to the AF out at the ACC socket being a fixed level. Luckily, the speaker I am using has a volume control on it, so I will have to get used to using that instead!
A nice simple project that took about an hour to complete, now I have a nice clean fixed line level audio feed from the 7100 connected to my speaker.