20ma current loop to RS-232 conversion

From TheRetroWagon
Revision as of 18:11, 20 August 2015 by Jeffa (talk | contribs) (Add my terminal strip colors)
Jump to: navigation, search

20ma current loop <> RS-232 conversion

Vintage PCB

Dig this crazy circuit board man! Still in it's original packaging from Hobby World Electronics in Northridge California.

TTY RS-232 Front.png TTY RS-232 Back.png

other resources

  • Another circuit. From [Altairclone] Specifically designed to fit in a Teletype model 33 using only a 12vdc wall wart for power.
  • Another circuit I found referenced on the greenkeys email list

My ASR hookup

Signal                      screw terminal          my wire color
---------------------------------------------------------------------
Transmitted data send (+)      7          orange
Transmitted data return (-)    6          brown

Received data send (+)         4          red
Received data return (-)       3          black