In addition to being concerned with microtonal and electronic music, he was perhaps the first to use the prepared guitar.
"Fongaard's output is considerable...Due to the partly experimental notation, these works have not become widely known.
He studied at the Oslo Conservatory of Music with teachers including Per Steenberg, Sigurd Islandsmoen, Bjarne Brustad, and Karl Andersen.
[1] He started off by constructing a quarter tone guitar with adaption of the fretboard, but very early left this in favor of a diverse set of prepared guitar techniques.
A sampler CD of his own recordings entitled Elektrofoni: Works For Micro Intervallic Guitar 1965-1978 [2] was released in 2011.