VOIP Audio Tools for Ham Radio

I like to operate my FT-817 remotely over my local LAN and have been using IPSound to carry the audio for many years. This has worked great using Ham Radio Deluxe 5.x to control the radio tuning, etc. however I was thinking there must be something out there that will work with my iPad by now since IPSound is a Windows only application.

I figured I would look for a Open Source Voice Over IP (VOIP) application and found one called Linphone. Linphone is one of many SIP telephone applications available. What interesting is I have seen Hams using Wifi Mesh applications like Broadband-Hamnet and connecting ATA phone adapters like a Grandstream HT701 so they can talk over the mesh. They of course are using a analog phone and to dial each other you just use the IP address of each station, but why do that when you can just use a softphone like Linphone. You can setup the contacts and you will not need to remember IP addresses, etc. I guess depending on the analog phones they use with the ATA adapters they could have memories in the phones. The analog phone do make it simpler to use if it were needed in some emergency communication situations.

Anyway, I did successfully get Linphone running on my Windows XP PC that I use to control my FT-817 and another copy on my iPad. The only thing I discovered is that I could not achieve the same audio quality as IPSound. I tried all the Linphone CODECs and the best one was the G722. For standard HF radio use this is fine. There may be better CODECs available as plugins but I have not yet pursued that direction.

Since Linphone is multi-platform it makes it very handy (e.g. Andriod, IOS, Linux, Windows, etc.) There is also a command line mode that I have not tested yet. All in all this seems like a usable solution and I will use it to monitor some of the HF nets for the next few weeks.