All,I am using an annunciator panel that currently uses 387 lamps (24vdc). I will be driving these annunciators using FSBUS and the LED driver board. What I am looking for is an LED package that will fit in the same mount as the 387 lamps but meet the current requirements for FSBUS. Can anyone assist? I have looked through Mouser/Digikey, but the problem is that there are TOO MANY choices! (So easily confused!).Any assistance is appreciaited.

Welcome to my hell!387 Lamps are Aviation lamps with a T 1 3/4 base. They run from $0.75 to $4.00 EACH. I have 100 switches that take 1-4 of these a piece!Since they are incandescent...they are HOT when all on...especially the 24v ones.LED's are definitely preferred for the cockpit.MY SOLUTION:I found a distributor who sold me 150 lamps for $0.75 each ~$120. I then picked up 150 White and Yellow BRIGHT LED's off of Ebay for $35.I set up a soldering/desoldering apparatus and separated the bulbs from the base...and then soldered in the LED. They fit very well. (need to be careful with polarity - positive in base for me)So...I got my 'LED 387' for about $1.00 each in costs + 13 HOURS of labor!I'll post some photos of the process if you'd like later this week.

That's great,... I have certainly thought about doing the same, and I know that I will save a chunck of change by taking the same route. My problem is that I have about 20 projects on the sim that take 13 hours and I really want to fly the damn thing! So I am looking to pick up the right LED's for the mounts. I know these are pretty expensive, but nevertheless...

I looked for LED replacements for the 387 (T 1 3/4) and they run from $5 to $16!! With the need for 100, the 13 hours didn't seem so horrible.some LED 387 sourceshttp://www.ecgi.net/t1mgb.htmlhttp://led.net/datasheets/Pages/470nm_super_blue/92a.htmhttps://www.netdisty.net/DS/BSD-1884/default.asp387 Lamp Source @ $0.79http://www.electronicsurplus.com/dictionary/cat1989.htmBest of Luck!

Thanks for taking the time to look around - I really appreciate it. I have seen these and similar items... the problem is that the direct replacement ones you note are for the 387 lamp, which means they are still 28VDC devices. The others I saw in one of your links require from 3.5 to 28 volts. Correct me if I'm wrong, but isn't the output of the FSUS LED Drivers something 1.5 vdc? Therein lies my dilemma! Finding something that will fit in that package and be usable with FSBUS.