I just put a video up on YouTube, showing how to load programs using the CASSETTE port at the back of the PPG wave 2.
This PPG wave 2 probably has a weak battery and loses its programs after a few months if it’s not turned on. The battery will eventually be replaced with a modern, non-rechargeable lithium battery and a diode.
Instead of using a cassette tape, I’m playing the data from my MacBook. The MacBook is set at 100% volume, the PPG seems to be very sensitive about the levels. The program audio that you hear in this video from 0:50 should theoretically work to restore the programs in you PPG. That’s why I chose to keep it at the right level, -5 dB, in this clip.