ATC-101 Port Powered RS-232 to RS-422 interface converter
The Model ATC-101 is a non-power RS-232 to RS-422 interface converter. The Model TBATC-101 has a DB9 Female connector for the RS-232 Interface and a 6 screw terminals connector or DB9 Male connector for the RS-422 differential input and output interface. MODEL TBATC-101 can convert the TD and RD signals of RS-232 into balanced full-duplex RS-422 signals.
ATC-106 Port Powered RS-232 to RS-485 interface converter (4-bit terminal)
ATC-106 (ATC-101) can covert the data from RS -232C to half duplex RS-485(RS-422) signal. It don't need additional power supply and can get the power directly from PC side. By it's "Automatic Send Data Line Control" function, you don't need to use RTS, just plug it and no need to install any hardware or software and work well under RS-485(RS-422) communication.

• Construction 
  ATC-101 Interface: RS-232 to RS-422 Converter  
  ATC-106 Interface: RS-232 to RS-485 Converter
• Connectors
  RS-232: DB-9 female 
  ATC-101 RS-422: DB9 male 
  ATC-106 RS-485 DB-9 male or a terminal block 
• Signals 
  ATC-101 RS-232 Side : DB-9 Female Signals: Use Pins 3 (TD) and 2 (RD).
  Pins 7 (RTS) and 8 (CTS) are tied together Pins 4 (DTR), 6 (DSR), and 1 (CD) are tied together.  
  ATC-106 RS-232 Side: Use Pins 3 (RD) and pin 2(TD also called SD) Pins 7 (RTS) and
  8 (CTS) are tied together Pins 4 (DTR), 6 (DSR), and 1 (CD) are tied together.  
  ATC-101 RS-422 Side : DB9 Male connector-PIN1 (T-) PIN2 (T+), PIN3 (R+), PIN4 (R-), 6 position terminal
  block -- +12V, GND, T+,T-,R+,R- Signals: Full-duplex 4-wire operation only Driver and Receiver are enabled
  all the time.  
  ATC-106 RS-485 Side: 4 position terminal block - 485, +485-, +5V, GND
• Data Rate: 300 to 115.2 KBPS, up to 4,000 feet at 19,200 BPS
• Operating Distance 
  Maximum Distance (feet): 4,000 6,000 8,000 10,000(using 24 AWG wire) 
• Power: powered from the RS-232 data TD or handshake lines
• Operation Temperature: 0° to 50° C, 5% to 95% relative humidity
• Dimensions: 88 x 33 x 17 mm