Chuck,
To decode a tty stream on a computer you can use either MMTTY
or another program called FLDIGI.
The tricky part is getting the audio from the web browser to the decode program.
In Win10 look in the Advanced sound options and in the decode program choose the audio device to match.
Another thing that can help route sound from one application to another is a program called Voicemeeter Banana.
If you have an android phone there is also an app in the Play Store called DroidRtty.
I have used that to decode iTTY but for some odd reason I could not get Tom's stream to play
on my Android phone. Your mileage may vary.
My experience has been that iPhones will not play Icecast audio streams so if you have an iPhone forget it.
Good luck,
-Steve