The Feedbridge FB11 is designed as an accessory to the Transmission Measuring Set TMS A11 allowing VOICELINK and other dedicated products to be tested. The Feedbridge FB11 is powered by the 50 V exchange supply. Active current sources provide the necessary high AC impedance for the line under test. The ring signal is not applied to the line if the line current is greater than 6 mA.

The following features are provided:

• DC current feed to a telephone line
• Ring generator with ring trip
• LED indicator for line current greater than 6 mA
• Reversing switch allows DC signalling