I have been experimenting with making interface units for use with NBEMS and handheld radios. They use a couple of isolation transformers and plug directly into the radio and the computer to make digital transmissions automatic and noise free. I currently have several units in various stages of production. If any locals would like one, please email me. I will sell them for the price I paid for the parts ($15-25 depending on options). See my blog post to learn more about them.