FDS OVH Panel Dual Brightness Annunciators Improvement

[sluyt050]

Hi all,

Although I am impressed with the overall quality of the FDS OVH panels, the 9 dual brightness annunciators could improve imo. With the present AN-1 boards containing a couple of diode's and a resistor, I find the difference between bright and dimmed marginal.

After some experimenting I found a simple way to overcome this. Instead of the 2 standard blue small angle LED'S, special FLAT-TOP LED's are used having an angle > 100 deg. For the bright state I use a white LED and for the dimmed state a blue one is used. Due to the large angle, the light of 1 LED is nicely distributed and even better than using 2 small angle LEDS. One can improve further by painting the housing white on the inside. 

For consistency I also modified the remaining 8 single state blue annunciators by using 2 (*) blue FLAT-TOP LED's.

FLAT-TOP LED's specification:
Diameter: 5 mm
Radiation Angle: > 100 deg.
Forward voltage: 3.2-3.6V
Luminous Intensity Typ Iv (mcd) : 4000 - 5000
Water Clear

Since the 2 anodes on the AN-1 board has to be powered separately now (white or blue), I slightly modified the board on the LED side (see picture). Diodes and resistor are no longer required. The same dual state connectors with 2 common black wires, 1 white and 1 green wire, can be used but it has to be connected to the 'normal' side of the board instead of the 'dim' side. For interfacing I use a FDS SYS1X board (very nice!).

I am very happy with the result which in reality looks even nicer than on the pictures.

Additional:
Dual Bright: location of the white LED at the normal side and blue LED at the dim side of the print.
(*) Single state: one blue LED will do if the housing is painted white on the inside.

[sagrada737]

Nice improvement Edward - I really like the increased contrast.  You have made some great improvements to your Sim!  Thanks for sharing.

Where did you purchase the LEDs ?  Do you have a part number?

Mike

[sluyt050]

Hi Mike,

I purchased them in a very small local shop here in the Netherlands. Unfortunately no part number or brand available. So you have to google for it.

[archen]

Amazing result!! Thanks for sharing. As I'm using phidgets I don't have a problem with dual brightness but I think the white led makes it look better so ill definitely give this a try.

Thanks again Edward 

[pierre24]

Nice improvement Edward - I really like the increased contrast.  You have made some great improvements to your Sim!  Thanks for sharing.

Where did you purchase the LEDs ?  Do you have a part number?

Mike

Hi all,
you can find these lesds on this website:

http://www.besthongkong.com/loose-led/5mm-wide/blue-led-120-degree-clear-wide-spread-angle-led

Regards

Pierre

[sluyt050]

I doubt if these are bright enough Pierre because I read Iv (typ.) is only 200-350 mcd. I will phone the guy from whom I buy them and ask him for details.

[archen]

I think I have some white LEDs to spare. I'll try them today and report back. They are high intensity and wide angle.

[sluyt050]

As I wrote, I ordered the LED's at a small internet shop here in the Netherlands. The link is: http://home.kpn.nl/fbakelaar/LEDS.htm

In principle mr. Bakelaar will only ship within Europe but for small items he is willing to ship outside the EU. I paid € 0.75 / LED for 10 LED's or more, shipping excluded. I understood they are made in the far east.

[archen]

Thanks a lot Edward! Tried it out and love it! Will desolder the blue ones and change them for white.

Anders

[sluyt050]

Thanks a lot Edward! Tried it out and love it! Will desolder the blue ones and change them for white.

Anders

Good to hear that you like the result too. I do not know if the FLAT-TOP LED's are also available in amber, they are made in green and red for sure. Could be interesting for FDS too since with these LED's only 1 per housing would do in general. So nicer lights at less cost, everyone happy! 

[sagrada737]

Here is a source for all kinds of LEDs - including "Flat Top" design.

http://lighthouseleds.com/catalogsearch/result/?q=flat

Mike

[sagrada737]

Thanks Edward for the constructive modification to the FDS dimming annunciators.  I purchased some of the flat-top LEDs you described and installed them in one of the spare annunciator PCBs that I had left over from my FDS Overhead Kit.  The results are quite nice, with a significant increase in contrast when the Valve is in transit.  Separating out the White LED for the valve-transit part of the display is just what the doctor ordered    The improvement in the annunciator display function is greatly improved.

I plan on getting some FDS annunciator PCBs and finish up the remaining Annunciators with this modification.  I don't want to hassle with de-soldering parts off of the current annunciators.

By the way...   The way the FDS SYS cards are designed, a single LED output will sink enough current to allow for up to 4 LEDs to be turned ON.  This technique is used in the AFT Overhead for the LE Devices display, and works well.  It's great that FDS had foresight to allow for greater capacity on the LED outputs.

Thanks again Edward for your innovation in helping to improve our Sim Projects.

Mike

[sluyt050]

Your are welcome Mike. Good that you found the LED shop.

[sagrada737]

Edward,

One thing I noticed (which you commented on) is that it is a good idea to paint the inside of the annunciator housing a reflective white, so the light from the two LEDs can "spread" more effectively.

In my case, I have already glued the front diffusers and nomenclature plates in place, so I left the housing as is.  Although the light spread is quite good without painting the inside of the housing, it would certainly be better is painted before assembling the parts together.  So...  For those doing this mod from the start, I would say definitely paint the inside of the annunciator housings.

Either way, this enhancement to the annunciator display is well worth considering.

Mike