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I liked the Longines Lindbergh watch but I didn't want to spend $4,725 to buy one so I decided to make my own. I went to the local Target store and bought a watch with a rotating bezel for $25.00. I used my Dymo labeler to make the one degree markings to put on the bezel, the numbers 1 through 15 spaced every four minutes, just like on the Longines bezel but minus the 15 ' labels between the numbers since I couldn't make numbers that small. So you just have to look at the minute marks after the numbered one on the bezel and remember that they represent 15, 30 and 45 minutes of GHA in addition to the whole degree value. This gives your the GHA accurate to 15'.

For the scale for the the additional 15 minutes of GHA that are read against the second hand I put Dymo labels on the clear plastic protective sheet that came on the watch. It can be removed and replaced and it clings to the watch crystal. 

The attached photo shows the watch indicating 01:08:45 GMT. I set the scales to today's equation of time of 3:40 by setting the bezel so that the "15" mark is aligned with the "3" minute line on the watch face. I then set the inner scale by peeling off the plastic protective sheet and sticking it back on with the arrow pointing at the "40" on the watch face for a total equation of time of 3:40.

So, to read out the GHA of the sun we look at the hour hand which is pointing at the "1" which represents 15 degrees. Next we look at the minute hand and see it is pointing at one mark past the "1" degree mark on the bezel so we read this as 1° 15'. Lastly we look at the second hand and see it is pointing at the 1' mark on the inner scale. 

Adding all of these together: 

180° 

  15° 

     1°  15'

          01'

------------

196°  16'

(You have to add the 180 because the sun is on the lower meridian at midnight. You could also consider the time as being 13 hours which multiplied by 15 equals 195.)

It ain't pretty but it works.

Looking at the almanac we find that the GHA of the sun at 01:00 GMT is 194°  04.8' to which we add the increment for 08:45 which is  2°  11.3' making the GHA 196°  16.1'  which confirms that he Lindbergh watch works to determine GHA of the sun.

I don't know how many of these watches they sold to 1930's navigators (not many if they cost the equivalent of $4,725) but there is a problem with their use caused by changes of the equation of time during the day. For instances, today it changes 32 seconds by tomorrow which would throw off the GHA by 8' unless the watch was readjusted every couple of hours. So you still need a list of equations of times for every couple of hours and, of course, you need a list of declinations too so you can't completely eliminate the almanac. 

gl