Hi Ed,
First, I was wondering, how do you get the audio from the sound card? Is it from a LabWindows program? I've never done that. Second, I was wondering how do you play the audio on the remote machine? Is that through a LabWindows program? I've never done that either.
But I was wondering if just a remote PC app would do the job. Like admins use to take over your PC from there desk and fix problems. I assume they have these that send the audio thru the net as well as the screen. Then on the radio's PC you just need a LabWindows program to control the radio and some other app to play sound from the sound card input to the local speaker. Then the remote PC app would magically transfer the screen and audio from the radio PC to the remote PC.
Otherwise, I can just say that to stream the audio thru the net, after the Radio's PC gets it off the sound card somehow, I would just set up two TCP servers on the remote PC, one for audio and one for the commands/control. When the remote PC client connects to the audio server the audio server would just start sending audio data to the client. The client would receive the data and put it in a big buffer to handle network speed variation. Let the buffer fill up to like a second or more worth of data before having anothe function/thread read the buffer data and give the data to the client PC's sound card. Big problem is that the client PC's sound card will alway's consume the data at a slightly different speed than the servers sound card produces it. Different clocks running at slightly different frequencies. So the client function that reads the audio buffer to give it to the sound card must play games. If the buffer is shrinking over time then it has to create extra samples to give to the sound card, just duplicating a sample every 100 samples or whatever. If the buffer is growing over time then it throws away a sample every 100 sample or whatever. So it's kind of a challenge to manage the buffer with the variable speed of the net transfering data and the two different rates of producing and consuming the audio data.
LabWindows has the TCP server create and client create functions so that's pretty easy. The harder part is that you probibly want to set the Radio's PC to a fixed IP address so that you can connect to it without worrying about domain names and such. Then the two TCP ports that the LabWindows uses for command and audio might need to be setup in all the routers to let you establish a connection. Your IT guy's can answer that.
PS. you can play around with this suff on one PC by using the RegisterTCPServerEx function and setting the local host address to "localhost", or "127.0.0.1" on one LabWindows project and using the corresponding ConnectToTCpServerEx with "NULL" as the server host name on another LabWindows project. This creates a virtual TCP connection on the same machine. This does not duplicate the different audio clock issue I talked about above.
