Programming an 82S23
Does this help you? http://gamearchive.askey.org/General/Data_Sheets/generic1_prom/ 

I searched for Signetics Generic 1 fusing procedure.

Also, according to the datasheet on the page I linked, the programming supply current is up to 500mA (at Vccp of 8.75V), and the current into the data pin being programmed is up to 200mA (at Vopf of 18V). So I would expect the chip might get warm, as it is dissipating almost 8W (8.75V*.5A + 18V*.2A).