With 10 seconds of data, there was a lot of horizontal scrolling to do.

Shown above is the first pattern to emerge, a 154 mSec. gap followed by two 137 mSec. gaps. A small code change to the digitizer and it waits for a 150 mSec. gap before it starts capturing data. Breaking the capture on the 154 mSec. gaps, then stacking the pieces another pattern appears. This time, every 60th cluster of pulses contains a 4.56 mSec. logic high.

Here is a closer look

Every block looks to start with the same double spike and gap pattern, could that be a preamble for Manchester encoding? Days of toying with this idea yielded nothing but decoding errors. Also, assuming the preamble represented four bit durations, the data lengths appeared to be about twenty bits. How odd.

The breakthrough came when I split the data on 10 mSec. gaps and stacked those segments.

Supposing that the starting pattern is 4 bits, then each line ends up being 32 bits wide. That sounds more reasonable.