Can you ID this instrument panel bulb?

[OrangeCrush]

Some of the gauges don't light up on my Yanmar Type C panel. Not the warning lights, just the little glowing lights that illuminate the three gauges for night passages. Does anyone know what bulb this is? Yanmar was no help, and it doesn't look like anything else I can find online. Thanks very much

[ohgary]

Looks like a 12v red LED similar to https://www.amazon.com/Paneltronics-...&s=hi&sr=1-100

[jstevens]

For my Yanmar panel the part nr is 600 824D. Not sure if that is a Yanmar or VDO part.

John

[jstevens]

In case you need it, the part nr i have for the lamp socket is 600-823D.

John

[Dsanduril]

I'm guessing you can get them cheaper elsewhere, but you can get a 4-pack at Fisheries Supply.

https://www.fisheriessupply.com/vdo-...ed-4pk-600-824

Edit - Just noticed the out-of-stock notice

[OrangeCrush]

Originally Posted by Dsanduril

I'm guessing you can get them cheaper elsewhere, but you can get a 4-pack at Fisheries Supply.

https://www.fisheriessupply.com/vdo-...ed-4pk-600-824

Edit - Just noticed the out-of-stock notice

Thanks, all. I heard back from VDO and they were able to provide some clarity. Turns out the 12v red bulb (600-824) has been discontinued and they only make the 24v (600-822).

I’m gonna see if I can make one of the similar ones from amazon fit the socket. If not I’ll probably just opt for the VDO white bulb (600-809).

[hellosailor]

Try an automotive parts store or a speed shop. There are all sorts of "instrumentation" bulbs that they carry for basically the same instrument clusters in cars. If you can email a picture of the existing bulb to DigiKey or Newark Electronics or Mouser, they also carry all sorts of electronics and may recognize the bulb.

Sometimes the instruments and bulbs are very carefully matched, so the light is diffused evenly only with the correct bulb. So if you can match it, that may be easier in the long run. You might want to replace them ALL while you are at it and have access, since the other ones will be aged out anyway.

And technically, if what you get is listed as an "instrumentation" bulb, that means it may be lower brightness but the filament is designed for extra long service, i.e. it may actually be a 15-volt bulb or simply a heavier filament structure. Worth paying a little extra for, unless you can convert to LED.

[a64pilot]

On my Maule Aircraft all the instrument light bulbs were literally painted red as red was I guess cool in the 80’s when my aircraft was built.
As ideas have evolved and dim white light is now what is considered to be best for aircraft instruments, I simply scraped the paint off.
If all you can find is a white bulb, paint it, sounds nuts but it really does work.

[OrangeCrush]

Originally Posted by a64pilot

If all you can find is a white bulb, paint it, sounds nuts but it really does work.

Jeez why didn’t I think of that?

[Simi 60]

Have at it


https://www.ebay.com.au/b/Red-5-mm-L.../bn_7037730747

I bought these ones.
$1.29 for 10 of them

https://www.ebay.com.au/itm/10pcs-20...edirect=mobile

[a64pilot]

Originally Posted by OrangeCrush

Jeez why didn’t I think of that?

Because it’s dumb, that’s why, your smarter than that
I couldn’t believe it when I took apart one of the lights and found that.
If I hadn’t seen it with my own eyes, I wouldn’t have believed it.
Of course it was FAA approved too as it had to be in the drawing package.

[Jim Cate]

Use of red fingernail polish on regular bulbs was SOP when I first had any instruments on a boat. I reckon that if we'd had the internet then, folks would have been arguing about
hot pink" vs "dusky rose" being best on your compass!

Meanwhile, when the lamp in my previous boat's Danforth binnacle compass died, I just wired in a generic red LED with a dropping resistor. Better light than the original, and was still working years later when I sold that boat.

Jim

[GordMay]

Originally Posted by hellosailor

Try an automotive parts store or a speed shop. There are all sorts of "instrumentation" bulbs that they carry for basically the same instrument clusters in cars. If you can email a picture of the existing bulb to DigiKey or Newark Electronics or Mouser, they also carry all sorts of electronics and may recognize the bulb...

The VDO #600-824 is a Type D T1 Wedge Bulb (1.2W 12V Red).

[hellosailor]

a64-
The myth of the red bulb for night vision has long been debunked, even if they still have their uses. Some companies used to sell "bulb dip", a special transparent colored coating for bulbs, designed to let more light through and not to burn up from the heat.
And someone had once given me a GE "Mazda" series bulb, actually blown from red transparent glass, that was for darkroom safelight use. I don't recall seeing any instrument bulbs made from colored glass, although "ruby" or "cranberry" glass for ornamental things and (scales on) lab glassware was not uncommon.
IIRC fingernail polish can char and discolor if the bulb is really bright and hot, which an instrumentation bulb shouldn't be. I suppose in an aircraft, if it was certified with tungsten bulbs and you put in LEDs the FAA might protest? ;-)

[Dsanduril]

I don't think you can dismiss red quite that easily, as a general light probably yes, but research I have seen says that for the specific task of maintaining general night vision while reading details on an instrument a long wavelength (~700nm) red light is the preferred choice.

Long wavelength red engages the central cones that are responsible for precise vision while hitting a "blind spot" in the rods around the exterior of the eye. The rods can only provide moderately detailed vision, so choosing a red wavelength for instruments allows you to see detail at the lowest possible level of illumination. For cabin lights a fully dimmable white or blue-green seems preferred, but for instruments in particular red is still king. Compass lights and other instrument lights still benefit from red. And with LEDs it is now much easier to specify a specific wavelength so you don't end up with a more general 550-600nm red that excites the rods too much.