TEX uses only the TFM file, which will produce if it's in a font-making mode. (The book, Appendix F.) Most DVI drivers read the PK font format, but makes a GF (Generic Font) file. So we need also to apply the GFtoPK utility:
gftopk myfile10.300gfto produce the wanted `myfile.300pk' (or, on MS-DOS, `myfile.pk') PK font.