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What means HVxxxx, etc


ArtMan
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Check out this page

http://www.ngs.noaa.gov/PC_PROD/DDPROC4.XX/dformat.htm#A.11

 

There is a reference to PID numbers under 3.3.1 field 3. While it is not clear, they would seem to be assigned simply in alphanumeric order, AA0001..ZZZZZZ.

 

You have 'AA' in Virginia which makes sense since expansion in this country was east to west. Here in Sacramento, CA, I deal with a lot of 'JS' prefixes.

 

Just a guess... I may be wrong.

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In my travels thru the database, I have noticed a few things about the PID.

 

- They do get assigned in groups, so you may have a group of similarly prefixed benchmarks in your area. In fact, they may even be sequentially numbered, especailly along railroads, making an interesting quest for someone to get a long list of sequential PIDs.

 

- Even though they are grouped together, a single area will probably have several different prefixes. My guess is that a state or an area is assigned a prefix or a range within a prefix to use until it runs out and requests another range from the NGS. I have seen the same prefix used in widely different areas, leading me to think that it is a range that is assigned, not a whole prefix.

 

- The web site that Silverado mentioned is very interesting. New PIDs are assigned as new stations are loaded into the database. This disagress slightly with the sequential nature of PIDs, but it could be that the initial assignment of PIDs was done when the database was already quite large and new ones are assinged as they are loaded according to pre-defined range.

 

- Here's a real strange one - PIDs in the southern part of the US seem to start with keys on the left hand part of the keyboard. As I am moving north, I am find more and more PIDs starting with the right hand. It's pretty consistant.

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