Friends,
In my last posting on this subject I described hooking up a 5 meter
string of LEDs to a small variable power supply and showing the results.
To me it was quite encouraging and I elected to proceed.
There was some question as to using that power supply in an aircraft as
it was a VPW (Variable Pulse Width) unit. These VPW units are notorious
for introducing considerable electronic noise into aircraft electrical
system. Another variable power supply had to be located.
Eric Jones, proprietor of Perihelion Design, advertised his
Extraordinarily General Purpose Adjustable Voltage Regulator, hereafter
referred to as the EGPAVR, as a low noise variable power supply for both
incandescent and LED lamps. Here is his documentation for the unit:
I ordered a unit which arrived in very short time and connected it up to
my power supply and the LED string.
Here is a picture of the EGPAVR connected to the power supply and the
LED string with the power out to the string coming from the variable
output (yellow lead) of the EGPAVR:
Here is a picture of the EGPAVR connected to the power supply and the
LED string with the power out to the string coming from the constant
output (green lead) of the EGPAVR:
It all seem to work quite well for my application. I plan to use a
short section of the LED string to back-light my fuel sight gage. Power
for this LED string will come from the variable output. The remainder
of the LED string will be used to illuminate the tunnel area of the
Europa and thereby serve as an interior work light. Power for this
string will come from the constant output of the EGPAVR. I=92ll have to
add an inline switch from the constant output to the work LED string.
This is so that the interior work light doesn=92t come on every time the
sight gage is illuminated, it can be turned on only when needed.
Now, if only it will warm up enough for me to get back to work in the
hanger. It has been quite cold here in N.TX. I=92ve tried a couple of
the warmer days to work but still froze. And there=92s no way that
epoxy will set up in this weather. So I work at home in the shop on
other projects.
Next posting on this subject will happen when I have had time &
temperature to install the LED strings and EGPAVR in the aircraft.
Blue skies & tailwinds,
Bob Borger
Europa XS Tri, Rotax 914, Airmaster C/S Prop (50 hrs).
Little Toot Sport Biplane, Lycoming Thunderbolt AEIO-320 EXP
3705 Lynchburg Dr.
Corinth, TX 76208-5331
Cel: 817-992-1117
rlborger@mac.com
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