Real battery switch turning off Real gear lights

Help creating logic scripts for Air Manager Instruments

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jph
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Re: Real battery switch turning off Real gear lights

#31 Post by jph »

It's called a 'back of a fag packet' design -I think that may translate badly to yank speak as 'fags' are cigarettes in the UK - and they are something else in yank land :lol:

Just a small edit, change the pull up resistor to 1K. (not critical),

You should only need the 'budweiser' size fire extinguisher for that one ...
:)
Joe. CISSP, MSc.

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Re: Real battery switch turning off Real gear lights

#32 Post by jph »

Hey Kirk You can pwm the 15V supply now with that set up and dim the bulbs !.. built in dimmer.
Just apply a PWM signal to the arduino pin that goes to the ULN. Instant dimmer.
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Re: Real battery switch turning off Real gear lights

#33 Post by jph »

Just thinking out loud, do you have a 33 ohm resistor ? -
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Kaellis991
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Re: Real battery switch turning off Real gear lights

#34 Post by Kaellis991 »

jph wrote: Sun Sep 25, 2022 3:44 pm Just thinking out loud, do you have a 33 ohm resistor ? -
I think I have every resistor value known to mankind.... ;)
The real rotary dimmer switches I added to my panel adjust the gear lights in the sim.
It wold be nice if that same hardware rotary switch also dimmed the real lights I have.
Never thought about it before....but it would be a nice add-on.

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Re: Real battery switch turning off Real gear lights

#35 Post by Kaellis991 »

jph wrote: Sun Sep 25, 2022 3:40 pm Hey Kirk You can pwm the 15V supply now with that set up and dim the bulbs !.. built in dimmer.
Just apply a PWM signal to the arduino pin that goes to the ULN. Instant dimmer.
Since the 15v is also driving the magnets, I wouldn't want to reduce the voltage to those.

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Re: Real battery switch turning off Real gear lights

#36 Post by jph »

That wouldnt be an issue really as you can power the magnets from 15v BEFORE the mosfet which would remain at 15v even if the output from the mosfet was lowered with pwm. It is certainly not the best mosfet driver circuit for PWM but it would work reasonably well with a change in pullup resistor and a low frequency drive. I was merely considering what you could do with it if you wanted :D

As a note, can you add a 33 ohm resistor (between 30 and 100 ohm, anywhere around there) between the mosfet Gate and the uln2803a pin. It just acts as a buffer when the gate capicitance is discharged. Not a big deal and nothing to do with dimming ;)
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Kaellis991
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Re: Real battery switch turning off Real gear lights

#37 Post by Kaellis991 »

jph wrote: Sun Sep 25, 2022 5:51 pm That wouldnt be an issue really as you can power the magnets from 15v BEFORE the mosfet which would remain at 15v even if the output from the mosfet was lowered with pwm. It is certainly not the best mosfet driver circuit for PWM but it would work reasonably well with a change in pullup resistor and a low frequency drive. I was merely considering what you could do with it if you wanted :D

As a note, can you add a 33 ohm resistor (between 30 and 100 ohm, anywhere around there) between the mosfet Gate and the uln2803a pin. It just acts as a buffer when the gate capicitance is discharged. Not a big deal and nothing to do with dimming ;)
That makes sense...thanks

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Re: Real battery switch turning off Real gear lights

#38 Post by jph »

I was just thinking and realised that you are driving the gear lights from the uln2803 driven by a mico ouput pin so you can dim them anyway without a mosfet, just pwm the inputs to the uln for each gear light. Instead of a hw output add use a hw pwm add. You have had dimmjng possibilty all along :D . The voltage at the bulb will be proportional to the pwm duty cycle percentage . The darlington pair in each uln output is your pwm power transistor in this case.
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Re: Real battery switch turning off Real gear lights

#39 Post by jph »

As mentioned above, you can 'dim' and high current / high voltage circuit (within reason) with the ULN2803A by using PWM on the input.
Do you have normal 'bulb' lighting for the original parts you have ?. In a lot of cases, depending on power consumption, you can wire several to a single pin on the ULN, also, you can wire many inputs on the ULN together for a single pin arduino control of dimming multiple ULN outputs.

One thing though regarding landing gear lights on the real aircraft - do the landing gear lights actually dim ?
As they are a warning light, they may be either on all the time at high brightness, or possibly have a slightly dimmer setting for when the panel lighting is on - for night use.
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Kaellis991
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Re: Real battery switch turning off Real gear lights

#40 Post by Kaellis991 »

The gear lights in the sim, and i assume the real aircraft, can be dimmed using the left hand rheostat on the switch panel both in the sim and by the hardware I installed in my switch panel with the LUA code. That switched pot activates the wingtip nav lights (no dimming on the nav lights) and then it dims and brightens only the (3) green gear indicator lights but not the in-transit yellow light. The right side rheostat dims all of the lights on the gauges and the radios, but it has no effect on the gear lights.

Each indicator for left, right, nose and transition are handled by a premade script that has coding for each light. That code has an output pin for each light independently, thus the 4 ULN outputs they are connected to.
Of course it would be more realistic if that potentiometer I installed in my panel could somehow dim not only the "inside the compuer sim" gear lights but also those real 12v lights powered by the psu.
The coding for that is beyond my capabilities right now, but I am getting a better handle on the LUA scripting. Perhaps by the end of the year i can figure that out.

I keep referring to my real gear lights as 12v but in actuality the LED bulbs are labeled as 14v, so I actually have my PSU set for 14v output which is a good voltage for the magnets also.

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