NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Kollsman periscopic sextant mount
From: Paul Brewer
Date: 2015 Jan 3, 21:00 +0000
From: Paul Brewer
Date: 2015 Jan 3, 21:00 +0000
Dave, the right hand bulb in your shot possibly came from an RAF Mk 1 or 2 periscopic sextant. They are the only ones I have come across with the mat black paint and a red dot.
I have used ultra bright LEDs to replace similar bulbs in Mk IXs to great effect, I would have thought a better way to go. 240V on a dark damp night is asking for an exciting time.
Paul.
On 3 January 2015 at 20:26, David Pike <NoReply_DavidPike@fer3.com> wrote:
I see that a firm claims 3V midget flange bulbs SX6S 3V 40 are available in the UK with a long delivery time and at great cost. However, the current is 40mA the same as the 28V bulbs in the US Kollsmans. If Watts = Volts x Amps, does that mean the 3V bulbs advertised will only push out 1/9 of the light of the 28V bulbs, or is the relationship less linear than that? In other words might I be better looking for a 240-28V power supply than fiddling around with 3V bulbs? What about ultra- bright leds? I suspect they're very directional and difficult to filter even if they'd fit down the holes. Dave
