This a name i think we are all familiar with. We have used them for many years and they claim to be 20% extra brightness etc etc,
This about the 3rd time we have this happen to us not only on the A1/232 but also on the A1 231. This was a brand new bulb 3 months ago and the projector its being used in has had a new, (a new old one) bulb holder and tested thouroughly.
We put our films on tonight and the first thing i said was "that picture is shite, its way too dark", i thought maybe the heat shield hadn't gone up, nope that was fine. After the first cartoon before the feature i let it cool down, unplugged and removed the nice new bulb
The pins are gleaming like anew silver coin, so it aint the bulb holder, there is nothing wrong there everything is all clean and looks new one look inside and this is whats happened, AGAIN. What causes this? Any ideas? I know it doesn't happen every day but it has only happened with Osram bulbs. All the inside of the filament is black. We only ever use the machine on the low bulb setting to preserve the life etc but 3 months???


Hey look, you can see me taking the pic

check the voltage at the pins Tom.

These lamps are superb. If it's a dull light output I'd be astonished if you traced this back to a bad batch of lamps.

We'll see.

Where did you buy these from Tom?

Might also be the cellar/basement at this time of the year?

Is this where these are kept?

Nothing electric ever likes damp or humidity or moisture in general you must remember!

Cold and dry is fine.Cold and wet is disastrous!

Hey Andy, i bought the bulbs around 3/4 years ago from Paul.
This is number two out of 4, (the first one was indeed a bad holder but this has been replaced & sorted), i keep all the bulbs in my bedroom wardrobe. The bulb hasn't actually blown it still works but obviously its totally unusable.
One of A1 231's fitted to my Brothers Eumigs, (he has no basement area), but it was exactly the same, the inside of the filament looks all black. That was last year.
Hoping it's just of couple of duds.

Mate that's real bad to read. I've never had any issue honestly!

Lamps arn't cheap nowadays. We need a minimum of 50hrs from each of them.

I swear by Xenophot lamps.

I will send you a 232 out on Monday when I'm off.

Keep the pj in your bedroom until you try this one.

This will hopefully serve us to get to the root cause.

I've used so far two out of a batch of twelve of these lamps supplied to me last year.

So far, no issues whatsoever.

I await the response eventually on this one.

You're a seasoned Vet Tom so I hate to even ask this, but to eliminate any obvious possibility I feel it needs clarifying.

Do you use a cloth to fit them?

100% every time. never a bare finger.

I knew it hand on heart Tom.

One to try gratis in the post Monday Tom.

I hope you report back 50 hours plus from it!

Andy, thank you, i'm embarrassed, i must pay for this!

You needn't be Tom, I simply want you to find out whether or not you have been sold a faulty batch of lamps or perhaps the problem lies elsewhere.

This action will go some way to identifying this I hope.

Osram lamps ??, where they made ..........., I have often suspected the origins of lamps some can't get at these price's, like the esc24v 200w lamp for the elmo, you can't get them from anyone now.

Osram lamps are manufactured in Germany Paul.

As said, I've never had an issue with any of mine, only the lampholders themselves from time to time.
This can be observed from minute one by the arcing across the pins or the fact they begin turning blue.
In extreme cases, this leads to erosion of the pins themselves due to arcing.

Put one of these on the end of your lamp, soldered back to source of origin, you're good to go for many a happy year I've found!

eehhh???
Whats thats Andy?

What's what Tom????

Are you asking what the picture is of?

this bit

Put one of these on the end of your lamp, soldered back to source of origin
I think im having a blond moment! I just pop the bulbs in and leave them till they blow

It was referring to a particular kind of lamp holder (B&W 881) Tom for anyone experiencing premature lamp failure.

This obviously doesn't relate to your issue here as you've recently changed yours and the lamps are not failing as such, just blackening?

This is something I haven't experienced aside from when a lamp capsule has actually blown.

Does it make any difference where you store them ?, I mean they are encased in glass, as is the reflector, which looks like its seen no work at all, they look tarnished after some use. This looks like a failed lamp because of faulty manufacture, possibly a leaking lamp envelope at the base maybe ???. All lamps have a shelf life, the gas molecules inside are
smaller than the glass molecules and so are escaping out through the glass. This looks like a lamp that has oxgen ingress, which will effect the tungsten element. You see this especially on floodlight lamps when they prematurely fail, the filament hits the glass and blackens it, just as Tom's photo .

You may very well have nailed it there Paul. They are four years in Tom's possession but who knows when they were manufactured?

I know lamps can last for a very long time in storage, but I'd imagine it has to be good storage conditions, just like anything else.

As you say, I'd probably suspect a manufacturing sealing defect now with these of Tom's.
Very rare though I have to say.

We'll see how he gets on with one from the batch I have. None have caused any issue so far I'm pleased to say.

Please PM me your address again Tom so I can send you the Osram A1 232 in the morning thanks.

Hi Tom, if you want the lamp to test your m/c with, it's here. I just simply need your address again.

It may be a few days now before I can post again sadly.

Hi Andy, did you get my PM?

I got a PM from you Tom, but not one with your address on it for me to post it out to you mate.

How odd
New pm now being sent

Got it thanks Tom, see new PM mate.

Tom, I've just had another lamp go on me this morning while watching my recent Robin Hood film through now it's back on 2 x 1200ft reels.

I can't remember the last time I changed a lamp out though on this my main projector, but I'm certain it was a considerable time ago.

This again is one of the ten off batch I ordered at the same time around this time last year. I still have six left and one went out to you, so I'd be very surprised if yours doesn't give you similar service time.

Let me know as you go and I will post a photo or two here of the pins, reflector and filament capsule after I've allowed it to cool sufficiently.

I'm almost certain I'm getting well over the quoted 50hr lifespan from these and there is no evidence on screen to suggest brightness levels are dropping off either towards the end of the service life of these lamps.



Above: During lamp cooling process before removal.

Below: As soon as removed...

Will do Andy, but i think its time for me to say on here, beware of the bulbs that were advertised on here not too long ago. Cant remember the name but i am sure most of you will know.
These are old shit stock with pins that are corroded before you take them out of the box. They are cheap for a reason and i will never ever trust anyone selling on here again,(or any other forum) who isn't a regular poster.
Came on, advertised, made money and F****d off again.
I sent a cheque which bounced, (i sent the wrong bank cheque), he quickly PM'd me and i sorted it there and then via PayPal as a gift so he wouldn't get charged a fee.
What a tosser i was, i should have sent them all back again.
Lesson learned. BEWARE if he advertises on here again. They are shit. you have been warned.
Andy,
Thank you very much, the osram is still going strong.