Delco Carousel IV-A INS CDU/MSU

[Ravamar]

> I have the MSU reverse engineered - switches, lamps and wires, easy as you say.

Are you willing to share the info you retrieved? Which pin connects what? It would be extremely useful!

> On my MSU the Bat/Nav lights are accessible from the front.

By unscrewing the transparent red and green plastic "covers"?
I fear I could damage them...

> Only replacing a backlight bulb requires disassembling the front panel.
Did you managed to detach the mode selector knob?

Question: Did you try to light up the bulbs? How many Volts? And...AC or DC? Do you think they could be powered up from an Arduino?

> My actual plan is to reverse trace connections from switches and seven segment displays to motherboard, then design
> new PCBs to drive all from the mobo connectors. Jackpilot said to have some diagrams, but seems dormant at this
> time.

Interesting! But are you planning to power bulbs with a separate power supply?
I was also looking into the possibility to take out the "primitive" 7 segment displays and substitute them with real 7 segment displays but there are problems with commas/apostrophe and the right hand N/S and E/W "icons"...

NOTE: I don't know if we are actually abusing of this forum. If so I'd have no problem creating a new "Hardware" forum on Simufly.com. Please (admin?) let us know!

[flightpanels]

A bulb is agnostic to AC / DC, either will do. Nowaydays a DC voltage is convenient with switch mode power supplies. IIRC the Bat/Ready bulbs are 12 V at least. Test by slowly increasing a power supply measuring Volts and Amps. Backlighting is 5V for sure.

Yeah, you unscrew the red and green plastic covers. The knob came lose by using a Inbus/Hex allen wrench. Many of these screws are multispline, successfully destroyed by people inserting inappropriate Inbus/Hex allen. In that case your only resort is careful drilling out.

The seven seg displays are not multiplexed, I guess each bulb to oprate at 4 - 5 V 20 mA. Yeah, you need a real 2 A power supply here.

[Ravamar]

Hello Jörg,

so, from what I understood, you are willing to retain all the bulbs (those simulating the 7 segment displays).
What about if a bulb breaks, how do you fix it?

My plans are to substitute everything (all bulbs) with LEDs and/or real 7-segment displays.
If possible, of course
I want (would like) to have everything working at 5V. Big problem will be to put LEDs inside illuminated CDU keys...

Questions for you:

a) Are you going to use it with MSFS or xPlane?
b) What are you planning to put inside to drive everything? RPi? Arduino? Custom electronics?

Thank you,
Marco

[Ravamar]

Jörg,

here (http://www.dtic.mil/dtic/tr/fulltext/u2/a264521.pdf) there are some (very few) details about CIVA INS electrical supply. Hope this helps...