Steve,

The way I went, before I spent more money than I could afford on an outboard effects unit, was to route the tape master out into the pc soundcard (I needed twin audio plug to mini stereo jack lead) and using Cool Edit (demo available from the Syntrillium site) converted to a .Wav file.

You can then manipulate the file using, if I remember rightly a maximum of two effects with the demo, Cool Edit.
Then play it back out to tape or use the .wav file to burn a CDR.

I hope this is of some use

Cheers

Gary