| Loop Limit | 4K ohms max. at 48VDC (5K meter - 26Ga non loaded) nominal 15mA minimum loop current |
| DC Resistor | 150 ohms Typical at 80mA current |
| Monitor Impedance, Ring Position | Low impedance - 600 ohms Typical at 1 KHz |
| Monitor Impedance, Monitor Position | High impedance - 100K ohms Typical at 1 KHz |
| Rotary Dial Output, Pulse Rate | 10 +/- 0.5 pulses/sec |
| Rotary Dial Output, Percent Break | 60% +/- 2% |
| Rotary Dial Output, Interdigital Pause | 8.5ms Typical |
| Rotary Dial Output, Leakage During Break | > 50k ohms |
| DTMF Output, Tone Frequency Error | +/- 1.5% |
| DTMF Output, Level of Tone Pair | +2 dBm max., -8 dBm min. |
| DTMF Output, Low vs High Tone Difference | -4 dBm max |
| Dimensions | 9 in x 2 in x 2 in (22.86 cm x 5.08 cm x 5.08 cm) |
| Weight | 0.82 lb (372.28 g) |
Designed to facilitate the installation, servicing and maintenance of analogue telephone lines, this telephone butt set offers all the essential testing functions, including dial tone detection, call making and receiving, high impedance monitoring and tone and pulse modes.