Abstract
We studied on performance improvement of TTM(TI21 Test Meter) that is test and diagnosis devices for jointless audio frequency track circuit on Korean electric railway TI21 standard. Upgraded devices is AD-TTM(Advanced TI21 Test Meter). This can measure alternating frequency USB(Upper signal band) and LSB(Lower signal band). In the audio frequency track circuit, ±17[㎐] of nominal frequency are demodulated and supplied to track relay through AND gate. It is important that measurement function which is error between USB and LSB. Need of AD-TTM will stand out in the electric railway system because this is simple and accurate rather than the former device.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
