LEDLIGHT.com

[Bitsyncmaster]

I bought one of these to check if they used the switching regulator.

https://www.ledlight.com/festoon_39m...md_12_vdc.aspx

They don't use any regulator but a resistor so they should work fine with my dome unit. These are made in China so I don't know if they last a long time. They are very bright. They have the diode bridge so are not polity sensitive.

Following currents with voltage measured across the "bulb" terminals.

14.0 volts = 137 ma.
13.5 volts = 121 ma.
13.0 volts = 104 ma.
12.5 volts = 88 ma.

The 39 mm festoon is a little long for the stock dome fixture but bending the "fingers" in the fixture and they then fit fine. The lenth tip to tip is 1.548"

This vendor has a lot of LEDs to choose from. If the specification for voltage is 10 to 30 volts, it's most likly a switching regulator controlling the current.

[DMCVegas]

Brightness is good, but how well do they fully illuminate the interior? I ask because the stock incandescent bulbs have a 360° beam to ensure that as much of the interior is washed with light as possible. While these are only 120° beams. Granted the light is recessed, but I was wondering how it compares.

[Bitsyncmaster]

Brightness is good, but how well do they fully illuminate the interior? I ask because the stock incandescent bulbs have a 360° beam to ensure that as much of the interior is washed with light as possible. While these are only 120° beams. Granted the light is recessed, but I was wondering how it compares.

I can't compare because I have built my own dome light LEDs about three years ago. If these were available at the time, I would have used them instead. LEDs are improving so much lately. These are made up of "5730" type LEDs which are 1/2 watt each. There are two strings of 3 LEDs and each string has a 39 ohm current limiting resistor. I would have made them without the diode bridge and bump the resistor up a few more ohms so current would not change so much with voltage changes. The diode bridge drops voltage and wastes power just so they work both directions.

You really can not look at the LEDs when they are on because they are so bright. One of my dome unit customers is going to try them. He was using the SuperBright 3710 bulbs but those are switchers so it causes problems with my dome unit. You also can not dim switching regulators very well with PWM.

[Bitsyncmaster]

My customer is very happy running these new LEDs with my dome unit. I did not get info on if it's brighter

"And they WORK BEAUTIFULLY with the Dome relay! Thank you for helping me narrow that issue down!"