John, 'belo' is quite common usage where I was in Porgera as church services are announced by blowing through a long PVC tube making a trumpeting sound, 'taim long go harim lotu, ol i winim belo nau' you ask if the source word is the English 'bellow', but I had always (perhaps mistakenly) thought that 'belo' was from the English 'bell' due to the church related usage. Jerry