0000 'C64-TAPE-RAW'
000C UBYTE[4] For future use...
0010 ULONG data length (Intel format LSB,MSB)
0014 UBYTE[] data 
...

Each data byte represent the length of a pulse (the time until the c64's hardware triggers again).
The length is (8*data) cycles (PAL C64), i.e. the data byte of 2F represent (47*8/985248) seconds.
The data byte value of 00 represents overflow, any pulselength of more than 255*8 cycles.

