NavList:

I have emailed you a pdf file concerning the use of the Hughes MkIX bubble sextant. I purchased my Mk IXA from LtCdr Luyck (sp?) at Infocenter about 12-15 years ago, and have been very pleased with it. Given time I can come up with some tests he performed with it, and comparisons of its accuracy with others--it performed quite well in its price category.

 

The present lack of a bubble does not necessarily indicate a ruptured or dry bubble chamber. Bubble formation can be tricky at first. The correct bubble size is important, also. When you are through using the sextant for the series of sights, the pressure on the knob controlling bubble formation and size should be released. This size control knob will often seem quite stiff when tightened.

 

The averaging mechanism typically runs for two minutes. It should not be used at all on land-based sights, only when you are on an observing platform that speeds up and slows down, thus changing bubble position..

 

Ken Gebhardt (sp? again) at Celestaire is certainly familiar with this model. Years ago I purchased from him a few of the grain-of-wheat bulbs this model uses.

 

I will look to see what I have besides the pdf file.

 

Good luck!

Marvin