The TRQ-1 is a simple testing device designed to indicate the status of the various pins of an EIA574/RS232 data port.

 There are two rows of bi-colored LED's (red or green) monitoring pins 1 through 4 and 6 through 9 (pin 5 is common). The data pins (2 and 3) have separate green and red LED's to better show the faster DATA pulses. All of the LED's glow green when indicating a low (mark) and red for a high (space). A +9 to +12 V is considered a high and a -9 to -12V a low. If no voltage is present then there is no illumination and if the DATA LED's (pins 2 and 3) show both red and green, then DATA is present.

The connectors are standard DB9-F and DB9-M, which are wired pin to pin, making the TRQ-1 bi-directional. The internal resistance at each of the active pins is approximately 3,000 ohms. Because the TRQ-1 is intended for use with EIA574/RS232 levels it is limited when testing for balanced RS422/485 or unbalanced TTL signals.

The TRQ-1 is a simple testing device designed to indicate the status of the various pins of an EIA574/RS232 data port. There are two rows of bi-colored LED's (red or green) monitoring pins 1 through 4 and 6 through 9 (pin 5 is common). The data pins (2 and 3) have separate green and red LED's to better show the faster DATA pulses. All of the LED's glow green when indicating a low (mark) and red for a high (space). A +9 to +12 V is considered a high and a -9 to -12V a low. If no voltage is present then there is no illumination and if the DATA LED's (pins 2 and 3) show both red and green, then DATA is present.

The connectors are standard DB9-F and DB9-M, which are wired pin to pin, making the TRQ-1 bi-directional. The internal resistance at each of the active pins is approximately 3,000 ohms. Because the TRQ-1 is intended for use with EIA574/RS232 levels it is limited when testing for balanced RS422/485 or unbalanced TTL signals.