Help on the Link 4+0 circuit

[jpp412]

Hey Austin et al:
I am new to this forum and am interested in building the link4+0 for personal use.

1. However, I am somewhat new/inexperienced with this type of thing. I don't see any identification of the parts required to build. Most of them I can figure out by looking at the previous design but not all of them.

2. Why can't this be used for up to 8 phones?

Any help would be appreciated!

Thanks,
Joe

 

[jpp412]

Has anyone built this circuit that could help with my questions?

Also, I noticed another circuit ("8-line telephone intercom") posted by someone else - is that a better design for me to try instead of the link 4+0?