The BARC remote radio has now been in operation for over a year and a half. We have club members using the remote who are in the Boulder area as well as members who are at times at some significant distance from the remote radio. Distance from the remote radio via the Internet does not appear to present any problems so far.
The operation of the station has been made easy for the user by choosing straight-forward-to-use software. The user has to make two connections to operate the remote radio/PC from his/her home PC. One connection is the control link which is used to control the radio and the PC attached to the radio. The other connection is an audio path between the user's home PC and the remote PC. The control link is a variation of VNC which allows the user to gain control of the remote PC and operate the PC as if it were in the same room with the user. The PC attached to the radio has the software to control the radio. The user thus uses that control software remotely. Ham Radio Deluxe is a popular (for good reason) radio control program. HRD is one control program we have in our PC. Since the radio we use is a Kenwood TS-480, we also have the Kenwood TS-480 software in the PC as well. The Kenwood software gives the user complete control of the TS-480 remotely and is usually the software of choice by our users.
The audio path is Skype which turns out to be a very respectable VIOP service which turns out to be highly tolerant of less than perfect Internet connections. Both the VNC software and the Skype software are free and available off of the Internet to anyone.
There are two interfaces that connect the PC and the radio. The control interface is an RS232 interface. Since most computers today do not come with an RS232 interface, we have added a PCI card with an RS232 interface. Most current radios require an RS232 interface today. This will change with time. The audio connection is made using isolation transformers in the audio path from the PC to the radio as well as another isolation transformer for the audio path from the radio to the PC. Both transformer outputs have attenuators to reduce the audio signal level. The amount of attenuation was tailored for the radio and for the PC sound card. If we change either the PC or the radio, we will likely need to change the attenuator settings as well.
Interestingly the biggest challenge for our remote radio operation has not been any of the above. Our remote radio is remote and does not have any Internet access. So we had to create a link to the remote site to get Internet to the site. The details of this link has been where the challenges for us have been.
Remote radio operations have evolved for more than 10 years and we are enjoying current software and technology. We have chosen the software solutions we are using because they are straight forward and free downloads for the user. The evolution with continue and as better solutions come along we will consider them and evolve too.
Don, N0YE