I just bought a detector this year for 30 usd. Not totally convinced of its
accuracy. AAMOF I'm kinda confused by the whole concept: bitter is not the
opposite of sour in my mind. I guess below 7 is sour; above 8 is bitter;
but in the 7 range is sweet? I have slightly bitter Hawaiian soil, but have
been composting of late. AIUI different plants have different values for
ph. Post what you're likely to plant and I'll try and see the target range.

Sand is a good drainage system for thick soil, but I would be weary of
adding it (atleast from the beach) as the salt would presumably drive up ph
levels. I remember reading somewhere that they were doing that in Ireland
right before the potato blight set in. Does 'thick' soil mean you have
puddling? Composting is supposed to remedy that.