Can you/How to convert GPS From Loran?
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Spectre
Contributor
I'm definately not an expert on this stuff by any means.
The -easiest- way is to use loran to get to the site, and then take a GPS waypoint
There is software out there that will help you convert [e.g. search the web for 'posaid2'], but from what I understand, it's not incredibly accurate [but I also understand that loran numbers aren't very accurate unless you are using the same unit that got the numbers]
The couple times I've tried converting Loran to GPS, I did it when I had 3 loran numbers in the waypoint. converting the 3 crossing points gave me a triangle somewhere on the order of 200 yards by 150 yards by 100 yards. I never got out to the site to figure out where the actual wreck was in that area though.
The -easiest- way is to use loran to get to the site, and then take a GPS waypoint
There is software out there that will help you convert [e.g. search the web for 'posaid2'], but from what I understand, it's not incredibly accurate [but I also understand that loran numbers aren't very accurate unless you are using the same unit that got the numbers]
The couple times I've tried converting Loran to GPS, I did it when I had 3 loran numbers in the waypoint. converting the 3 crossing points gave me a triangle somewhere on the order of 200 yards by 150 yards by 100 yards. I never got out to the site to figure out where the actual wreck was in that area though.
Most nautical charts have both the LORAN lines (big arcs) and Lat/Lon down the sides for
GPS or sextant.
Most marine GPSs can input LORAN TD's. Some setup is required -- you have to tell it
which LORAN stations you are inputting TDs for. RTFM.
You do need to remember than while LORAN positions are very repeatable (same
numbers will get you to the same spot) they aren't very accurate when converted to
Lat/Lon because the radio waves can be warped by things like mineral content in the
bedrock, and the conversion will reflect that inaccuracy. What I would do is convert
the LORAN numbers with GPS, then go find the site, and move the GPS waypoint as
required. Note that in the same general area, all the conversions will be off by the
about the same amount, so once you find the first, the rest will be easy. But I'd
convert now, just in case that old LORAN unit goes belly up.
GPS or sextant.
Most marine GPSs can input LORAN TD's. Some setup is required -- you have to tell it
which LORAN stations you are inputting TDs for. RTFM.
You do need to remember than while LORAN positions are very repeatable (same
numbers will get you to the same spot) they aren't very accurate when converted to
Lat/Lon because the radio waves can be warped by things like mineral content in the
bedrock, and the conversion will reflect that inaccuracy. What I would do is convert
the LORAN numbers with GPS, then go find the site, and move the GPS waypoint as
required. Note that in the same general area, all the conversions will be off by the
about the same amount, so once you find the first, the rest will be easy. But I'd
convert now, just in case that old LORAN unit goes belly up.
deadend
Guest
Go to offshorehunter.com for a program to convert the loran #'s to gps. This is supposed to be one of the best out there. Do a search on spearboard.com to see what folks think of it.
miketsp
Contributor
The official status of LORAN-C is at http://www.navcen.uscg.gov/loran/default.htm
in the last paragraph.
in the last paragraph.
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