TANDY 1000 TX (250-1600) Math Coprocessor Faxback Doc. # 1166 Note: Refer to Faxback Doc. # 1276 for Main Logic Board Layout. There is a socket on the main logic board at location U15 where the math co-processor is to be installed. All you have to do is plug the co-processor chip into the slot. Use an 8MHZ Intel 80287 Math Co-Processor. For information on the catalog number of the Math Coprocessor, refer to Faxback Doc. # 9002.