Go with Sipura 3000 instead of Grandstream HT-488.
Even though it only has a single FXS port (for one telephone), there are success reports of using it as a PSTN gateway for Asterisk.
There are no such reports for the HT-488, and I have been singularly unsuccessful trying to get it to work.
I have been very successful with their FXS adapters, but I cannot get it
to work for FXO.
But if you can afford it, a Digium TDM21B for $240 would definitely be the best choice if you can run phone wire from your Asterisk box to where the phone needs to be.
I have a one little question… the SPA-3000 has 1 FXO and 1 FXS. Let’s say I decide to upgrade my system later and get a second SPA-3000, that will mean I can plug 2 phone lines and 2 telephones in the system, right?
My question is, will Phone 2 (2nd card) be able to talk over Line 1 (1st line)? Can the computer route conversations from one unit to another?
I assume so, but I couldn’t find that information…