ITU-T K.21
Products as per Basic standards

Power Line Interference Generator YD-993G
- Description:Power line interference generator YD-993G is designed to simulate the interference generated by the power line to the signal / data lines through electromagnetic inductance or direct contact. 
 - Model:YD-993G 
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Coupling/Decoupling Networks for Surge Testing on Unshielded Unsymmetrical Communication Lines CDN 21AF8
- Description:The CDN 21AF8 is designed to couple surge pulses onto 8 lines (4 pairs) unshielded unsymmetrical communication lines for voltage 
 - Model:CDN 21AF8 
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