DTX-CHA001 vs. DTX-CHA001A vs. DTX-CHA002

For "in channel" measurements (shown below), you can use any combination of DTX Channel Adapters. 

DTX Channel Adapters Combination

You only need the DTX-CHA002 if you are making "channel to channel" (Alien Crosstalk) measurements. The DTX-CHA002 is supplied with the DTX-10GKIT (Alien Crosstalk Testing Kit). The DTX-CHA001 and 1A were revised to improve the random noise floor for Alien Crosstalk measurements and enhance accuracy. The revision has no impact on the "in channel" measurements. If you are worried about mixing adapters, the AxTalk Analyzer Software will not allow you to use the DTX-CHA001 when making Alien Crosstalk measurements.