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Re: Kollsman periscopic pendulous sextant
From: Gary LaPook
Date: 2008 Sep 1, 01:51 -0700
From: Gary LaPook
Date: 2008 Sep 1, 01:51 -0700
Here is the information about building a 28 volt power supply. Purchase the CC10-1212-DF-E for $26. Depending on how you hook it up you can choose any output between 24 and 30 volts. As is, it puts out either 24 or 30 volts (which is probably close enough for powering a sextant averager) but by adding a 10,000 ohm 1/4 watt resistor (25 cents at Radio Shack) you can get the output at exactly 28 volts. http://www.lambdapower.com/ftp/Specs/cc-e.pdf http://www.lambdapower.com/ftp/appnotes/cc-e_datasheet.pdf http://www.digikey.com/scripts/us/dksus.dll?Detail?name=445-2436-ND gl On Aug 31, 12:27 pm, glap...@pacbell.net wrote: > That is exactly what is used with the A-10 sextant, 4.5 volts from > three size "D" batteries. If you have one of the more modern Kollsman > sextants that use an electronic averager you do need to supply 28 > volts to the averager since they won't work on less. For use in an > airplane, you can make a 28 volt power suppy with one integrated > circuit and a small amount of soldering. The IC converts 12 volt DC to > 28 volt DC and costs about $25.00. I made one and can find the source > for this IC if anybody wants to do the same. You can also get 27 volts > out of 3, 9 volt batteries wired in series. This works fine for the > lights but the averager uses about 150 ma so these betteries don't > last long powering up the averager. And they are expensive. > You can also replace the 28 volt bulbs, or in your case the 3 volt > bulbs, with 6 or 12 volt bulbs that are the same size and power them > up with other battery combinations or with a cable to your lighter > socket in the plane. If anybody needs the source for these other bulbs > I can find it again. I think I posted all of this information on bulbs > and on the IC about a year ago so you can probably search the archive > for it also. > > gl > > On Aug 31, 6:56 am, wernerwrote: > > > Actually my Kollsmans are Euopean license builds (1 from Kollsman- > > Germany and the other 2 from Kollsman-UK, and had been used in the > > respective air forces). Those sextants have a 3 Volts lighting system. > > 28 Volts only go into the gimbal aircraft mount. Within it the voltage > > is transformed into 3 Volts to go into the sextant. The usual method > > (when not installed in an aircraft) is to use a modified flashlight > > (instead of the bulb there is a connector for a cable) with 3 D-cells > > (flashlights were provided in the storing case). > > > Werner > > > On 31 Aug., 04:49, glap...@pacbell.net wrote: > > > > BTW, if you need a 28 volt power supply for using your sextant at home > > > just go down to Home Depot and buy a water sprinkler system electric > > > transformer which puts out 28 volts and is cheap. > > > > gl > > > > On Aug 27, 12:12 pm, werner wrote: > > > > > Hi, > > > > Has anyone a manual for this sextant? I need one for the "non-bubble" > > > > type, but with the pendulum. I have three of these sextants (two good > > > > ones, one needs overhaul). > > > > > Thank you. > > > > > Werner --~--~---------~--~----~------------~-------~--~----~ Navigation List archive: www.fer3.com/arc To post, email NavList@fer3.com To , email NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---