GNU Radio text file sink

Question

I'm trying to teach myself basics of GNU Radio and DSP. I created a flowchart in GNU Radio Companion that takes a vector that is the binary representation of a single character (the character "1" as "00110001"), modulates, demodulates, and writes to a file sink.

The scope sink after demodulation looks like the values are returned (see below; appears to be correct pattern of 0s and 1s), but the file sink, although its size is 19 bytes, appears empty, or at least is not returning the correct values (I've looked at it in ASCII and Hex text editors). I assumed the single character transferred would result in 1 byte (or 8 bits) -- not 19 bytes. Changing some of the settings in the Polyphase Sync and adding a Repack Bits block after the binary slicer results in some characters in the output file, but never the right character.

My questions are:
Can GNU Radio take a single character, modulate/demodulate it, and return the same character?
Are there errors in my flowchart?

I'd appreciate any insights or suggestions, thank you.