Pepperidge farm remembers the array of five 1uf elecrolytic capacitors That would telltale a MAX232 (or similar) chip. The capacitors would switchively boost the 5VDC tail to +/- 10V (actually 12V was desired, but 10V was barely sufficient) to drive "RS232" ports - and modems and whatnot.
Pepperidge farm remembers the array of five 1uf elecrolytic capacitors That would telltale a MAX232 (or similar) chip. The capacitors would switchively boost the 5VDC tail to +/- 10V (actually 12V was desired, but 10V was barely sufficient) to drive "RS232" ports - and modems and whatnot.