In the 1990s W0EKV designed a beautiful QSK box but I cannot find the circuit description anywhere. I happen to have a copy of the "internal" and "external" models of that QSK Box, so I uploaded it to my web site and to the archive.org. gopher://sdf.org/d/users/djringjr/w0epv_qsk.pdf http://qsl.net/n1ea/w0epv_qsk.pdf https://archive.org/details/w0epv_qsk Nice unit. 73 DR