How to dim ems warning led?

[bbtapb]

I was thinking a signal relay connecting the main bus (w/resistor) to an LED anode and cathode direct to SkyView dim output. But, that's kludgy. Is there an option to pwm the ems light output?

 

[bbtapb]

Can someone recommend a simple transistor solution?

 

[GalinHdz]

Depending on which light fixture you used it can be as simple as a piece of semi-opaque tape. FWIW, I used a LEGEND LIGHT fixture from ACS and replaced the bulb with an LED from SUPERBRIGHT LEDs. Initially it was too bright so I put a small piece of semi-opaque white tape (Glider Tape) I had in the hangar inside the fixture. Simple, elegant and works very well.

You can see the external indicator light(s) just above the SkyView displays in this photo:

LEGEND LIGHT FIXTURE - http://www.aircraftspruce.com/catalog/elpages/legendlights.php
LEGEND LIGHT LABEL - http://www.aircraftspruce.com/catalog/elpages/legendlights3.php?recfer=18277
SUPERBRIGHT LEDS - https://www.superbrightleds.com/cat/ba9s-ba7s/
GLIDER TAPE - https://www.cumulus-soaring.com/bowlus.htm

 

[ChiefPilot]

Can someone recommend a simple transistor solution?

How about an NPN transistor such as the 2N3904? As long as the load is under 200ma or so it'll work fine.

 

[dynonsupport]

Are you trying to dim it only at night or all the time? Do you have another switch in the cockpit that you want to dim it via, or only via the SkyView auto light sensor?

If you want to use the SkyView PWM, you need a transistor, and the easiest thing to use is a FET. See the schematic below. Any small P-Channel FET will do, you don't need the one listed in the schematic.

The below assumes the LED is a "12V LED" with a built in resistor. If not, you need a current limiting resistor for the LED which can be on either side of the resistor.

 

[dynonsupport]

And if you really want to use a BJT instead of a FET, it looks like this

 

[bbtapb]

Desire is to dim it with just the SV PWM output.

First-class support.  Thanks!