>From RADIO Shack you can by a RS232 Serial Analyzer a.k.a. RS232 Mini-Tester. Its about 2 inches by 1 1/2 inches. It is a DB25 male to DB25 female with 7 LEDs. You put this adapter in line between your PortMaster and your modem. The lights indicate the status of...
TD - Transmit Data
RTS - Ready to Send
DSR - Data Source Ready
CD - Carrier Detect
RD - Receive Data
CTS - Clear to Send
DTR - Data Terminal Ready
It looks something like:
_ _
/ |--+ +--| \
/ .| | | |o |
|..| +-----------------------+ |oo|
|..| RS232 MINI-TESTER |oo|
|..| |oo|
|..| TD O O RD |oo|
|..| RTS O O CTS |oo|
|..| DSR O O DTR |oo|
|..| CD O |oo|
|..| |oo|
|..| |oo|
|..| |oo|
|..| +-----------------------+ |oo|
\..| | | |oo/
\_|--+ +--|_/