We have 4 HME DX200 in stock which we use frequently as single kit´s .Now and then we  put them together to get a bigger system. So we now have a Helixnet for test,to see if we could use it as an intelligent Matrix, and to get rid of echoes and hum.But we cant get it working with the 4-wire connections.And we only get the 2-wire connection to work if we put an Party-line Intercom main station between the DX200 and the Helixnet.How should we config the system to work proper, and is there an better box than the Helixnet to use as an matrix between the DX200's ? 

Answer: 

a) DX 200 to Helix-net via 2wire : Yes you're correct a Party-line power supply is needed between the DX200 and Helixnet main station when using the 2w connections See page 96 of the attached Helixnet manual 

b) DX200 to Helixnet via 4wire You need to make up a special 4wire crossover cable between the DX200 and the Helixnet main station See page 99 of the attached Helixnet manual 

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