We are looking into building an Asterisk <a href="https://www.asterisk.org/">https://www.asterisk.org/</a> PBX, and I was wondering if I would be able to salvage our Nitsuko phones.

The bottom of the phone says:

Do the phones follow some standard, or will I have to throw them away?

Nope.

Terse answer, but appreciated!

I was hoping that the phones were made to some standard -- ADSI, ISDN, or, too much to hope for, SIP, etc.

Sorry, I was in a hurry. Those phones are proprietary to Nitsuko i-series systems. Good luck with asyerisk..I have tried it out and it seems ok for simple stuff. The only thing is that if it's mission critical I wouldn'y do it unless you own the company or want to be unemployed.

Without knowing the architecture of the Asterick, I can only say that if it supports single lines, the only way you can use your Nitsuko phones is to keep the Nitsuko KSU, and feed the single lines from the asterik to the CO ports on the NIT KSU.