Re: Datasette not loading I know very little about Tapecart, but I don't remember reading about it having any kind of 264 series support. However, if you are willing to add a proper firmware interface for plus/4 and C=16 machines to it and write a native browser, I think you will be celebrated for the great achievement.
Re: Datasette not loading Well, it seems that no amount of azimuth adjustment would help with that. Now it is the time to either try it with another Computer and Datasette or start some serious troubleshooting with instruments.
Re: Datasette not loading Sorry if this is too obvious: when you press play, there's a cassette in the datasette right? You should be literally hearing what's on it. If it's a program file, then it's the "usual" screeching. (You can try the exact same thing in YAPE as a test, attach any TAP file and "listen" to it.)
Re: Datasette not loading Before you possibly ruin your azimuth alignment, you should check if any remotely detectable signal is coming from your Datasette at all. There was a miniature Assembly programme that you could even type in in Monitor to check signal presence. Unfortunately, I completely forgot what it was. Could someone please help?
Re: Datasette not loading Invest in a Sd2iec drive. They are not expensive. Old hardware is becomming unreliable. Except you are really enjoying fixing them.