How to easily view LCD screen in an AV-bay

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May 26, 2015
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I wanted to easily view the LCD screen of a Marsa 54L altimeter contained in the AV-bay of a Wildman 3 inch Dark Star without the need to take the AV-bay apart. This was done by using a rotatable 4 inch wide switch band that was held in place by an epoxied 1/2 inch switch band just forward & aft of the movable 4 inch non-epoxied switch band (see photo A). When open the "viewing window" is 3 x 2.5 inches-enough room to see the entire LCD screen and to easily access the 2 screw switches that turned on the 2 altimeters (photo B). When closed, the rotatable switch band was fixed in place by a 6-32 machine screw (just visible in photo A) that screwed into a small (flat) weld nut epoxied inside of the coupler tube. In this way, its easy to both turn on the altimeters while on the launch pad and quickly view the LCD screen pre- and post-flight. The AV-bay vent holes were drilled into the aft 1/2 inch switch band.

A. AV-bay closed.PNG B. AV-bay open.jpg
Although I initially thought this was a novel approach, a search of TRF revealed that Steeve (aka Crumb fire) originally posted this idea some time ago. Subsequently, I did email Steeve and he made several helpful suggestions. Construction proved to be less difficult than expected via the use of hose clamps and a Dremel.

Fred, L2
member of ICBM
Camden, S.C.
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