Good question. I will try to find out an answer for you and get back to you. I also have a KLN 94 installed in my airplane and I bought a special card reader that let me update the data card by downloading the data from the B/K website. I bought it off eBay about 12 years ago. It worked well but it doesn’t appear that the guy selling them has any more.
I also typed KLN 94 into the eBay search engine and a few years ago found someone who was selling datacards that were one cycle old (not up to date but very close). I bought one because I hadn’t updated for quite a while and that got me in the ball park. Not legal for IFR but a lot better than what was in my 94. After I installed the new card, I sent him my outdated one.
