3854-H BULB BLOWN

[357mag1]

I was breaking in a new ROP bulb using 6.4volts (4 Nizn in series with mdocod adapter). When I checked on it after 30 minutes the bulb was milky white and dead. I broke the last 3854-H in the same way and now run it with two Li-ions in series and it works fine. Did I get a bad bulb?

Just wondering if others have had a similar experience?

 

[LumenHound]

Did I get a bad bulb?

Yup. You got a lemon. It's rare but it does happen.
The gas inside the bulb leaked out and oxygen leaked in.

If your interested, Icebreak's Race to Failure thread is a worthwhile read for anyone wanting to learn about the different types of bulb failures that can occur.

 

[357mag1]

Thanks for the info. I recharged the batteries and inserted another 3854-H bulb which survived 30 minutes with no issues. I'm new at playing with Icans and wondered if my technique was flawed.

 

[Illum]

if the lamp turns white...or blue, its a lemon

the white is Tungsten Trioxide, purple-blue is Tungsten Blue Oxide, either way it indicates oxygen has gotten into the envelope.

my experience with 3854-H failures only work two ways. Lamp either burns out, usually turning black or it instaflashes, and burns out with the globe clean. There is the third outcome involving a damaged reflector, but I've never had it happen with my ROP lamps

 

[DM51]

Good to see a thread about the ROP - a CPF milestone mod pioneered by KevinL, still going strong.

 

[ANDREAS FERRARI]

Thanks for that link DM51!

I was out in the woods just after midnight and opened the the trunk of my car.Out of the 2 dozen lights I had with me I chose a DBS Aspherical and a 2C ROP-High.That ROP lit up the bush for nearly 2 hundred yards!Still a great concept after all these years.I always wondered who came up with the idea until I saw this thread.......

ROP owners sign in.

Maybe time for new owners in sign up.

 

[357mag1]

Re: 3854-H BULB BLOWN (UPDATE, ANOTHER DEATH)

I have broke in one ROP High and have been running it with no issues using 6 14670 AW cells with 2 sets of 3 in parallel for a total of 7.4volts (8.4 max).

Thinking I would set a ROP up for longer runtime and life by keeping it at 6.4volts (4 Nizn in series) hasn't worked well for me. The second bulb has now died but in a totally different fashion. I was demonstrating the light to my wife after doing a proper break in of the bulb when it quite working (during turn on). The resistance across the bulb leads measured 130 ohms not open like I expected. The filaments look fine seems like something might have happened in the potted base.

I now have number three (on Nizn's) up and running. Hopefully this will be a success.

 

[Kestrel]

Thanks for that link DM51!

+1, that might have been the beginning? :thumbsup:

The ROP is the only incan that has ever really gotten me interested enough to really play around with them - a very inexpensive pastime. What a perfect combination of parts, especially for 'sleeper' lights like old chrome-plated Rayovacs or the cheap plastic 2D lights at work.

 

[mrartillery]

or the cheap plastic 2D lights at work.

This is a cool mod, put a ROP low in a el cheapo plastic light, and when people turn it on they're like :huh:

 

[Illum]

This is a cool mod, put a ROP low in a el cheapo plastic light, and when people turn it on they're like :huh:

They do melt though if you leave it on long enough, and it wouldn't work with alkalines

the easiest and safest way for unenlightened people to have sleepers and "get it" is the 6D mag lamp and one of mdocods 6AA to 2D holders. Its not that much of a difference right? you should see the difference in the hotspot, the 6D magnum-star lamp even out-rivals the 6V lanterns with huge reflectors

 

[swampgator]

They do melt though if you leave it on long enough, and it wouldn't work with alkalines

the easiest and safest way for unenlightened people to have sleepers and "get it" is the 6D mag lamp and one of mdocods 6AA to 2D holders. Its not that much of a difference right? you should see the difference in the hotspot, the 6D magnum-star lamp even out-rivals the 6V lanterns with huge reflectors

I ROP'd a sixties era Captain, glass lens and metal reflector. A light just like grandpa had. Until you turn it on.

One of the best sleeper ideas, not that it was originally mine, but I stole it fair and square.

 

[Illum]

aww, nice collection piece too, you are holding a piece of history my friend:wave:

I ROP'd a sixties era Captain, glass lens and metal reflector. A light just like grandpa had. Until you turn it on.

One of the best sleeper ideas, not that it was originally mine, but I stole it fair and square.