NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Bubble sextant manual scanned, put on web
From: Paul Hirose
Date: 2006 Sep 7, 00:07 -0500
I have scanned the "Sextants" section of Air Force Manual 51-40, "Air
Navigation" (1955 and 1960 editions) and posted it on my little web
site. This is good info for owners of U.S. bubble sextant models A-10,
A-14/AN5851-1, A-15, MA-2, and Kollsman periscopic. The MA-1 pendulous
mirror sextant is also covered.
The page is 990 k, but 95% of that is the images. If you have a slow
connection, it may be best to turn off graphics in your browser, read
the text, and individually download the images you want.
http://home.earthlink.net/~s543t-24dst/airnav/index.html
My new HP C3180 did the scans. It's a combination inkjet printer,
flatbed scanner, and copier, priced at $100. This is my first experience
with a scanner. As far as I can tell, this unit does a good job,
especially considering its low price. To input text, I scan it in black
and white mode and request the output as a .txt file. (OCR software is
bundled with the unit.) Then I paste that into an HTML editor and clean
up the OCR typos by hand. The biggest problem by far is that a hyphen at
the end of a line invariably causes letter doubling. E.g., ad-ding (with
a line break after the hyphen) comes out as "addding". Nevertheless,
this process is enormously more productive and accurate than hand typing.
Some of the "typos" are exactly what the original says. For example, the
periscopic sextant section has a true heading formula: TH=TB-8RB [sic].
I haven't fixed those mistakes, since my objective is to accurately
reproduce the original.
The C3180 can produce *much* sharper scans than the images on the web
page, but more resolution means slower page loading, especially for
users on dial-up. In addition, the physical size of some of the images
on the screen becomes annoyingly large. So, I set the resolution just
high enough to generate adequate images, and some I omitted entirely
when I felt the text was understandable without them.
It's fortunate that AFM 51-40 is loose pages bound by metal clips. The
book comes apart easily. I imagine conventional binding would cause a
lot of trouble getting the pages flat on the glass.
I may put more of this manual online. If you have a burning desire to
see a particular topic, speak up. I have only one volume from the 1955
edition, but all three volumes of the 1960 edition. It captures an
interesting time in air navigation. The sextant, astrocompass, and
4-course radio range are in there, but so are VOR, TACAN, and Doppler.
--
I block messages that contain attachments or HTML.
--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to NavList@fer3.com
To , send email to NavList-@fer3.com
-~----------~----~----~----~------~----~------~--~---
From: Paul Hirose
Date: 2006 Sep 7, 00:07 -0500
I have scanned the "Sextants" section of Air Force Manual 51-40, "Air
Navigation" (1955 and 1960 editions) and posted it on my little web
site. This is good info for owners of U.S. bubble sextant models A-10,
A-14/AN5851-1, A-15, MA-2, and Kollsman periscopic. The MA-1 pendulous
mirror sextant is also covered.
The page is 990 k, but 95% of that is the images. If you have a slow
connection, it may be best to turn off graphics in your browser, read
the text, and individually download the images you want.
http://home.earthlink.net/~s543t-24dst/airnav/index.html
My new HP C3180 did the scans. It's a combination inkjet printer,
flatbed scanner, and copier, priced at $100. This is my first experience
with a scanner. As far as I can tell, this unit does a good job,
especially considering its low price. To input text, I scan it in black
and white mode and request the output as a .txt file. (OCR software is
bundled with the unit.) Then I paste that into an HTML editor and clean
up the OCR typos by hand. The biggest problem by far is that a hyphen at
the end of a line invariably causes letter doubling. E.g., ad-ding (with
a line break after the hyphen) comes out as "addding". Nevertheless,
this process is enormously more productive and accurate than hand typing.
Some of the "typos" are exactly what the original says. For example, the
periscopic sextant section has a true heading formula: TH=TB-8RB [sic].
I haven't fixed those mistakes, since my objective is to accurately
reproduce the original.
The C3180 can produce *much* sharper scans than the images on the web
page, but more resolution means slower page loading, especially for
users on dial-up. In addition, the physical size of some of the images
on the screen becomes annoyingly large. So, I set the resolution just
high enough to generate adequate images, and some I omitted entirely
when I felt the text was understandable without them.
It's fortunate that AFM 51-40 is loose pages bound by metal clips. The
book comes apart easily. I imagine conventional binding would cause a
lot of trouble getting the pages flat on the glass.
I may put more of this manual online. If you have a burning desire to
see a particular topic, speak up. I have only one volume from the 1955
edition, but all three volumes of the 1960 edition. It captures an
interesting time in air navigation. The sextant, astrocompass, and
4-course radio range are in there, but so are VOR, TACAN, and Doppler.
--
I block messages that contain attachments or HTML.
--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to NavList@fer3.com
To , send email to NavList-@fer3.com
-~----------~----~----~----~------~----~------~--~---