From Orange to Blue

[djoffe]

Lately, it seems that Blue LED's are all the rage. Here's a way to add them to a classic kit. I've made a small assembly of blue led's that fits in the space of a neon lamp. With a change in the dropping resistor(s), you can use it anywhere you would have used a neon lamp...

I haven't gone into production yet, but I figured people might like to see it.

From Orange to Blue

 

[godfrey]

Now all you've gotta do is stock up on neons for when people get bored with the blue and want to go back to the "classic" look. 😀

 

[overtheairbroadcast]

Will you offer them in different colours like green or in a low brightness level? Just curious as I find green less retina searing in the dark.

 

[CBS240]

What about one like this? You can have your choice of 3 colors or blend them in different intensities.

Actually I plan to use one of these in the next project to indicate...blue for stand-by, green for active, and momentarily switching to red for clipping indication; all in one indication.😛

 

[RJM1]

How much more current does it draw compared to the 0.3ma for a NE2 neon lamp?
How hot does the dropping resistor get when you operate it from 120V or 240V (overseas) AC power?

 

[RJM1]

Blue AC neon bulbs $ 0.50


Blue AC neon bulbs [BLUENEON] : LEDsales. LEDs, LED products and other cool stuff.

They also have green, yellow and white neon bulbs.

 

[djoffe]

RJM...

The DIYAudio forum is better than google! I had read that blue neon lamps were available, but when I googled them, never found a source. That's why I made this LED assembly. Right now, I'm running about 5 mA through it...It's probably too bright...I might eventually settle on 2.5 mA...but then, if this blue neon lamp looks good...maybe that's the way to go!

Thanks for the link!

Dan

 

[RJM1]

Previous link was Australia.
New link, Van Nuys, California.
Neon Lamp, NE-2B, 6x12, 60mm leads, BLUE NE-2B-6x12x60 - All Spectrum Electronics

Whole page.
Neon Lamps - All Spectrum Electronics
6x12, 6x20, or 6x24

 

[djoffe]

RJM1,

Thanks for the new link...closer is better....

I'm curious...how did you find these guys?

Dan

 

[RJM1]

Google search
ne-2 blue neon
8th down

 

[djoffe]

As that famous philosopher, Homer Simpson would say, "D'Oh!"

Thanks...

 

[RJM1]

A lot of the times with Google it's how you ask the question. Sometimes I have to rephrase, or just move the words around until they give me the answer I want.

 

[djoffe]

Brightness Experiments

At first, I put about 10 mA through the array--e.g. 120 V through 10K. It was quite bright...so I cut the current down to 5 mA-120 V through 20K. It was still pretty bright...

RJM1 pointed out the comparison with a Neon lamp...0.3 mA...So, I did some experiments...

50K resistor...about 2 mA - still looked pretty good.

90K resistor...about 1 mA - still respectable

150 K resistor...about 0.7 mA - still clearly visible as ON...maybe after losses through the "clear" plastic of the switch might be a bit dim...

Still...I was pleasantly surprised how low I could drop the current...

2 mA might be quite acceptable...that's only 240 mW off a 120 volt line. That's really quite manageable...

 

[Coconuts 500]

Blue LEDs used to be all the rage. It was very trendy from about 2001-2006. Now, white LEDs are where its at. Try to find something modern and trendy with blue LEDs today. Can't be done.

🙂

 

[tvrgeek]

I bought a little cheap amp with a tri-color LED. Fixed it right up with a set of side cutters. Ok, so I am over 15.

 

[qusp]

yep, loving the white for the last year or so, i'm a mac user you see. problem is that blue and even moreso white are much noisier than orange, red, green, yellow....

 

[djoffe]

I did some more experiments with the blue LED assembly in a Dynaco Stereo 120 power rocker switch.

I found that a 100K dropping resistor seems just about right...still nice and blue, quite well visible, but not so much light as to be jarring. My original version used a 20K dropping resistor...quite bright and blue...but too much...

I think it's the visual equivalent of subwoofer effect...people start out with their subs turned up way too high at first, and then gradually drop it to where it makes a bit more sense. So it seems, with the amount of blue light.

Another interesting measurement for the record...The original dropping resistor in the switch, for the NE-2 orange lamp, was about 33k (two samples measured 36K1 and 32K5). It looks like a 1/2 watt resistor was used originally. That's a bit lower resistance than I would have expected...I had in faded memory a typical value of 100K-150K.

 

[djoffe]

The Blue Light Kit is ready to go. Take a look here:

From Orange to Blue

 

[djoffe]

Here is the orange to blue light conversion for a PAT-4...I took a number of pictures...on most of them the color didn't look anything like real life. This one is the closest I could get...

Any photogs out there with hints about getting the right color balance to show the beautiful blue of the LEDs?