UK Vintage Radio Repair and Restoration Discussion Forum

UK Vintage Radio Repair and Restoration Discussion Forum (https://www.vintage-radio.net/forum/index.php)
-   Components and Circuits (https://www.vintage-radio.net/forum/forumdisplay.php?f=40)
-   -   Unusual light bulbs (https://www.vintage-radio.net/forum/showthread.php?t=197650)

G6ONEDave 21st Jan 2023 12:19 pm

Unusual light bulbs
 
2 Attachment(s)
I am attaching a couple of pics showing some unusual bulbs that I've come across whilst sorting through a large miscellaneous box full, hence some of my recent bulb sales.

From left to right the known info is GEC MES 2.5v 0.2a frosted, unknown re the frosted small push fit, 2.5v MES, green laquered MES 3.5v 1:6 Germany, red laquered unreadable but probably same as the green one, MES style but has 2 contacts on the base and 2 filiaments 0.5a Foreign the voltage is printed but dirty and I don't want to remove the remaining info. The last bulb is set inside a metal screw cap similar to the type used on old binding posts, can't see any rating on these.

Dave

broadgage 21st Jan 2023 2:58 pm

Re: Unusual light bulbs
 
The frosted MES bulbs used to be more common but are no longer readily available AFAIK. They had two main uses, firstly for minimal room lighting in premises without mains electricity, and secondly to light microscopes or other instruments.

The flat topped opal backed MES bulbs also used to be popular but are also no longer readily available. Used in small torches without a reflector, and also in wall mounted lights that used a type 800 cycle lamp battery. Useful fitted just inside the front door of houses without electric lights, or in dark areas.
Also fitted next to the fuse box in places with electricity. Some designs had a compartment to hold matches, fusewire or other items. Used in the war to light air raid shelters.

Nothing that unusual about the red coated bulb, most lamp makers offered superficially coated miniature lamps for a slight extra cost. Many applications, including Christmas lights.

Not seen a part coated lamp like the green one. Possibly done by the end user for some special need.

G6Tanuki 21st Jan 2023 3:23 pm

Re: Unusual light bulbs
 
That's an interesting collection! Several I've not seen before.

Does anyone remember the little squat MES bulbs that had a lens blown into the glass at the top, for use in the Penlight-type torches powered by a couple of 1.5V HP7 batteries? I think I've still got such a torch somewhere, I used to use it when peering around in the back of equipment-racks to trace cables.

60 oldjohn 21st Jan 2023 3:38 pm

Re: Unusual light bulbs
 
Then there is the 6v Pifco Lantern 6v bi-metal MES. That is is interesting when used in a scale light on a radio!! I have a box of the flat topped bulb in #1 bulb pic 3.

John.

Dave Moll 21st Jan 2023 4:31 pm

Re: Unusual light bulbs
 
Quote:

Originally Posted by broadgage (Post 1530306)
The flat topped opal backed MES bulbs also used to be popular but are also no longer readily available. Used in small torches without a reflector...

Very similar in appearance to the bulbs used in the Enigma machines.

Quote:

Originally Posted by G6Tanuki (Post 1530312)
Does anyone remember the little squat MES bulbs that had a lens blown into the glass at the top, for use in the Penlight-type torches powered by a couple of 1.5V HP7 batteries?

I've certainly owned these in the past. I don't think I've had one in recent years.

John10b 21st Jan 2023 4:42 pm

Re: Unusual light bulbs
 
I have seen/used them many years ago, nice to see them again.
John

60 oldjohn 21st Jan 2023 5:46 pm

Re: Unusual light bulbs
 
5 Attachment(s)
A few bulbs out of my box including closeups of the Pre-focus and flat face. There are two neon MES bulbs bottom left of last picture. I have a box of the white plastic enclosed bulbs, I have no idea what they were for. And a grain of rice I think, well its smaller than the grain of wheat.

John.

alfatangowhisky 21st Jan 2023 7:47 pm

Re: Unusual light bulbs
 
Plastic fronted ones are (were) used in control panel indicators

Lucien Nunes 21st Jan 2023 8:16 pm

Re: Unusual light bulbs
 
5 Attachment(s)
Here's an unusual lamp on an unusual cap. These were made for the illuminated stops on some Compton organ consoles in the 1930s-1960s, and pushbuttons on certain Compton-derived Strand lighting controls such as System C. These were in effect large illuminated momentary pushbuttons about an inch in diameter, with the subtlety of being double-touch (a second contact closes if pressed with extra force).

The lamp has a flattened envelope with a coiled filament forming a supported arc facing the front. The cap consists of a plain sleeve contact with a very long rigid wire emerging from the insulator forming the second contact. This locates in a small hole in the back of the switch body. The lamp does not move when the button is depressed.

The filament is under-run for long life and vibration-resistance and is as much a heater as a light - it dissipates a good fraction of a watt at 18V while giving out the colour seen in the attached pic. This example was borrowed from the 1937 Southampton Guildhall organ and is probably original. We will soon be changing them to LED not because there is anything wrong with the lamps, but to minimise the exposure of the plastic parts to heat as they are starting to deteriorate. On some heavily-used organs, the more popular stops are badly discoloured and damaged.

broadgage 21st Jan 2023 10:36 pm

Re: Unusual light bulbs
 
Quote:

Originally Posted by G6Tanuki (Post 1530312)
That's an interesting collection! Several I've not seen before.

Does anyone remember the little squat MES bulbs that had a lens blown into the glass at the top, for use in the Penlight-type torches powered by a couple of 1.5V HP7 batteries? I think I've still got such a torch somewhere, I used to use it when peering around in the back of equipment-racks to trace cables.

These are still available on ebay and elswhere.
Lamps for one or two dry cells are common, and those for three or four cells exist but are very rare.
Widely used by doctors who prefer the traditional incandescent lamp over LEDs.

A white plastic sealed disposable penlight is available for medical use that uses two AA cells and one of these bulbs.

emeritus 22nd Jan 2023 2:00 am

Re: Unusual light bulbs
 
A couple of years ago I bought a bag of ten 1.25V lens-ended MES bulbs in Chelmsford Market for £1. I don't have an immediate use for them, other than if I need to convert any of my existing torches that use lens-ended bulbs to single-cell operation.

broadgage 22nd Jan 2023 12:28 pm

Re: Unusual light bulbs
 
CP lighting have a good range of lens end torch bulbs, including the rare 3 cell/3.3 volt and 4 cell/4.8 volt types, also a lower current 2 cell type at 0.18 amp.

If you know anyone working in a hospital, they might be able to obtain dead disposable medical penlights. These are easy to break open and retrieve the bulb.

Maarten 22nd Jan 2023 2:23 pm

Re: Unusual light bulbs
 
If I were to manufacture disposable incandescent penlights, I would probably choose to run the bulb at a slight overvoltage to increase the brightness and colour temperature and to more closely match its life to the battery life.

In other words, if custom manufactured optimally, those bulbs might have little hours of life left.

duncanlowe 22nd Jan 2023 2:37 pm

Re: Unusual light bulbs
 
I have a few rechargeable torches that use those MES with a lens in front. I've replaced them with LED equivalents for more light and a longer run time.

emeritus 22nd Jan 2023 6:06 pm

Re: Unusual light bulbs
 
Possibly doctors prefer incandescent lamps because they produce a predictable continuous spectrum. I would think that the colour of tissues can be important when making a diagnosis, and doctors will be used to the appearance of tissues under tungsten illumination. It's like when my mum always used to view clothes etc. at the doors of shops in daylight rather than under the interior illumination produced by the old fluorescent strip lights.

G6ONEDave 23rd Jan 2023 1:03 pm

Re: Unusual light bulbs
 
Some interesting replies there and thanks to all contributors. Still like to know more about the bulbs on the right in my pic. The pair of metal cased bulbs could be from something ex forces and I'm guessing that the twin contact MES based one may have built in reduntency incase one side fails in action. Thats just a guess though.

Dave

broadgage 1st Feb 2023 12:03 am

Re: Unusual light bulbs
 
I think that the twin filament MES bulb might have been intended for use in lit navigation buoys for harbour entrances etc.

Use of two bulbs would be less satisfactory as they cant both be accurately focused. A more sophisticated arrangement was several bulbs mounted in a rotating holder, when a bulb failed the holder rotated the next one into place.
Made in sizes from less than 1 watt in E10 up to hundreds of watts in GES.

These lights used very large capacity disposable batteries, sometimes of more than 1,000 AH. Longer running than the 8 day oil lamps otherwise used, and simpler and safer than acetylene.


All times are GMT +1. The time now is 8:12 am.

Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.