B&H 16mm Sound Projector Exciter Lamp?

[Janice Glesser]

Do the B&H sound projectors use the same long BRK exciter lamps as the Elmo 16CL? If not, which lamp does it use and has it too been discontinued?

[Steve Klare]

Hi Janice,

These folks:

https://www.replacementlightbulbs.co...v75asound.html

Describe BAK (used in many B&Hs) as a substitute for BRK:

https://www.replacementlightbulbs.com/lampbak.html

Also BRS:

https://www.replacementlightbulbs.com/lampbrs.html

The difference among them is in the filaments: the volts, amps, envelope and base look the same. Hopefully any difference in filament location and geometry can be compensated for with a slight adjustment of the volume knob.

They have 613 BAKs and 247 BRSs in stock.

The good news is they are either 3 or 4 Bucks a Pop, so even if they don't work out it's not a huge loss!

[Janice Glesser]

Thanks Steve... You did answer my question 🤗Unfortunately the BAK will not work in the Elmo 16CL. The BAK isn't long enough. There are actually two sizes of BRK ... One short and one long. Only the long will work. I ordered a couple of BRK bulbs on eBay, but they turned out to be the short ones. The pictures are sometimes hard to tell the length.I can't see how you can tell the difference since I they don't have a different number.

I was thinking if I ever reach a point where I can't get a new exciter bulb for my Elmo then I would try to pick up another type of projector. I like the slot load projectors and I know Bell & Howell have this type. I just wanted to make sure it didn't use an Exciter lamp that was discontinued.

[Steve Klare]

Hi Janice,
The nice thing about Replacement Light Bulbs is the owner doesn’t mind helping people out with technical issues.

I bet if you explain the size issue with BRK, he can tell you pre-sale what he has in stock.

[Dominique De Bast]

I remember that in the '90s, someone had a batch of new Pathé Baby bulbs made, on special order. Maybe someone will one day do the same for exciter lamps?

[Janice Glesser]

I remember that in the '90s, someone had a batch of new Pathé Baby bulbs made, on special order. Maybe someone will one day do the same for exciter lamps?

I second that Dominique...that would be wonderful!

[Ed Gordon]

See: Best Exciter lamp for an Elmo CL ?

February 28, 2021, 02:44 AM

Mark

The filaments in the G27 and the G29 are vertical and horizontal respectively. The G27 works on its side (Eiki and Elmo), and the G29 works vertically (B&H and Bauer/Rank Aldis). They both have the same "skirt".

It's always a good idea to visually inspect before fitting. I once bought a Bell & Howell TQII quite cheap because it had low sound. When I got it home I discovered that someone had fitted a G27 instead of the correct G29. I fitted a G29 and was greeted with great sound.

Perhaps it would be a good idea to stock up on both lamps, they do seem to have a long life. I can't see any real alternatives at the present time.


Maurice

[Ken Finch]

It is so annoying that there was so little compatibility between projector manufacturers as far as lamps were concerned. It can be understood in the early years but from the late 1930s it was inexcusable to me but it still exists with video projectors in some cases I believe. 😒

[Lindsay Morris]

The BRS as the post from Maurice above states that the G29 bulb has the filament Horizontal within the envelope in relation to the base.

It will NOT work in the Elmo 16CL as the filament needs to be Vertical within the envelope in relation to the base.

The variations in exciter lamp types has to do with HOW the sound optics are configured...B & H for years have used the Horizontal filament layout even going right back to the very early sound machines with the 750 & 1000W lamps where the filament was driven by a high frequency oscillator to avoid hum in the sound. When that system ended with the start of the TQ series they moved to the 4V @ 0.75 A Dc with very good hum filtering in the power supply.

I have both a Elmo 16CL which looks to have G27 installed and has no type markings on it only are the maker and the fact that is 4V @ 0.75A. I have NOT used it for ages as the sound head rollers are perished and I do have a Elmo 16CL 250W Xenon used often which has a G27 bulb installed and in comparing the two bulbs in the Elmos they are identical so both are G27 lamps.

The BRK lamp has a slightly SHORTER filament as compared to the G27 which possibly is a BAK (cannot confirm that as the marking is simply G27).

The smaller filament size MIGHT produce a slightly lower volume so I will try a BRK in the Elmo Xenon and see what the results are like and post accordingly.
Watch this space.

[Lindsay Morris]

An Update...went to thread up the Xenon machine with a sound test film and the feed spool is VERY tight IE more or less jammed and I discover that the rewind gear with normally free wheels when projecting has a huge crack in it and will not allow the feed spool to rotate smoothly and is so stiff a bit of scrap film was shredded as I tried to run it thru...Damn.
Seems that Van Eck have a couple in stock so a test of the sound output with either exciter lamp in will have to wait until I fix that unless I can coax the ratty sound roller 16CL incandescent lamp equipped machine to run.
With a tone sound track I can measure EXACTLY (in dB) what the difference is, if any, between the two types of lamps.

[Terry Sills]

Janice
pm sent.
Terry