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RS-232 PockeTester
The Patton Model 51 DB-9 PockeTester™ monitors the seven most important async EIA-574 (RS-232 on a DB-9) data and control lines. Uses seven tri-state LEDs to indicate the presence of the following signals: TD, RD, DTR, DSR, RTS, CTS and DCD. A red light = Mark; a green light = Space; no light indicates no signal on the line. No AC power or batteries required.
Seven LEDs monitor RS-232 signals
All 9 Pins are wired straight through
Bright LEDs have great Color intensity and a wide viewing angle
Data bias can be inferred from the intensity of the Colors