4 FXS Port with SIP Trunk, Best method for phone connections

With the help of this forum I was able to get my 4-Port FXS card working great with my SIP trunk for both incoming/outgoing calls. We are attempting to do a PSTN free setup.

My friend is dead set on keeping his recently purchased RCA 4-Line phones. He also has a fax machine that he uses about twice a month. I’m racking my brain on how to set up his phones to the FreePBX box. To make it easy, I was thinking of just having one port per phone (with the last port having a splitter for the phone and the fax and will have a dedicated DID).

But then I was thinking, would this method offer kind of a BLF for these analog phones… If I were to combine the ports into two RJ-11’s for each phone (Line 1&2, 3&4) and have the extensions act as lines? This way it would be easier to tell who was on the phone if their “Line X” light was illuminated on the other phones. This would probably eliminate the hung group options, but I’m trying to keep it as old school as possible for this guy.

Any thoughts?

Just pretend your FXS ports are POTS lines for the purpose of connecting the RCA phones.


and then just have corresponding ZAP extensions for each “pots line”? (ZAP extension 101 for channel 1, Ext 102 for channel 2, etc…)
I’m probably over complicating things since I usually just use SIP phones lol


And…Congratulations!..You’ve just successfully converted a FreePBX/Asterisk system to a 1A2 Key System…(grin!!!)


But when the roof leeks the rain won’t get into the relays. And you won’t have to replace all the bulbs after a power surge.