When you set the reference for twisted pair tests, you usually connect the DSX main and remote testers together with a permanent link adapter and a channel adapter. But for some applications, only channel adapters are available. For example, for installations tested using DSX-CHA12 channel adapters, permanent link adapters are not available at this time. To set the reference without a permanent link adapter, use the DSX reference module to connect the main and remote testers together:
The reference module is included with the DSX-CHA12S adapter kit. You may also purchase the module, model name DSX-REFMOD, as an accessory.