The Parrot Echo Server is the best method for a station to test that the network is working end to end.
While “Polly” has here obvious audio testing value, the Parrot uses the single most resources across the widest parts of the network for 1 station. So if you can hear your transmission come back to you, then the network is likely working OK and your station will be heard on the other available talkgroups. If you are not sure you are getting out, then take “Polly” for a spin!
You don’t need a computer for this testing and you don’t need another station to respond to you…though those can be very helpful as well.