Switchboard Indicator Lamps

Paul Hovnanian P.E.

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Jun 15, 2018, 8:08:31 PM6/15/18

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I need some to restore some old telco equipment. The bulbs are a slide base,
24V 2W incandescent, similar to these:

https://www.grainger.com/product/LUMAPRO-Trade-Number-24PSB-21U505

but longer. The above lamps are 1-7/64" long (28mm). The lamps I need to
replace measure 43mm.

These things are OLD. The above Grainger bulb has a plastic wedge-shaped
base. The base of the lamps in this old equipment are wood.

Any ideas on sources or even the proper size/type name?
--
Paul Hovnanian mailto:Pa...@Hovnanian.com
------------------------------------------------------------------
If it wasn't for physics and law enforcement, I would be unstoppable!

N_Cook

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Jun 16, 2018, 4:01:13 AM6/16/18

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On 16/06/2018 01:12, Paul Hovnanian P.E. wrote:
> I need some to restore some old telco equipment. The bulbs are a slide base,
> 24V 2W incandescent, similar to these:
>
> https://www.grainger.com/product/LUMAPRO-Trade-Number-24PSB-21U505
>
> but longer. The above lamps are 1-7/64" long (28mm). The lamps I need to
> replace measure 43mm.
>
> These things are OLD. The above Grainger bulb has a plastic wedge-shaped
> base. The base of the lamps in this old equipment are wood.
>
> Any ideas on sources or even the proper size/type name?
>

I'm in the process of bulk disposal of my old shop stock, as you can see
from the last update date
http://www.diverse.ip3.co.uk/compfull.htm
in the UK though, as in the pic you refereed to.
IIRC they came from an aircraft repair facility , so maybe used in
cockpits also

Piotr Piatek

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Jun 16, 2018, 1:38:43 PM6/16/18

to

On 16.06.2018 02:12, Paul Hovnanian P.E. wrote:

> I need some to restore some old telco equipment. The bulbs are a slide base,
> 24V 2W incandescent, similar to these:
>
> https://www.grainger.com/product/LUMAPRO-Trade-Number-24PSB-21U505
>
> but longer. The above lamps are 1-7/64" long (28mm). The lamps I need to
> replace measure 43mm.
>
> These things are OLD. The above Grainger bulb has a plastic wedge-shaped
> base. The base of the lamps in this old equipment are wood.
>
> Any ideas on sources or even the proper size/type name?
>

Look for "Slide Base T6.8". For example SM2420G (24V 0.5W) are in stock
at Mouser.

John Robertson

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Jun 16, 2018, 2:57:52 PM6/16/18

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On 2018/06/15 5:12 PM, Paul Hovnanian P.E. wrote:
> I need some to restore some old telco equipment. The bulbs are a slide base,
> 24V 2W incandescent, similar to these:
>
> https://www.grainger.com/product/LUMAPRO-Trade-Number-24PSB-21U505
>
> but longer. The above lamps are 1-7/64" long (28mm). The lamps I need to
> replace measure 43mm.
>
> These things are OLD. The above Grainger bulb has a plastic wedge-shaped
> base. The base of the lamps in this old equipment are wood.
>
> Any ideas on sources or even the proper size/type name?
>

T-2 bulbs measure 1-11/16" in total length. You are looking for 24C1
Telephone and Indicator bulbs according to my old light bulb spec guide.
They are rated as 0.06 - 085A, 1900 Footcandles, average cold resistance
33R, hours life = 5000.

I might have those in my ancient parts stock if you can't find them
elsewhere.

At least you know what you are looking for now!

John :-#)#

--
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MOVED to #7 - 3979 Marine Way, Burnaby, BC, Canada V5J 5E3
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"Old pinballers never die, they just flip out."

John Robertson

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Jun 16, 2018, 3:00:18 PM6/16/18

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On 2018/06/16 11:57 AM, John Robertson wrote:
> On 2018/06/15 5:12 PM, Paul Hovnanian P.E. wrote:
>> I need some to restore some old telco equipment. The bulbs are a slide
>> base,
>> 24V 2W incandescent, similar to these:
>>
>> https://www.grainger.com/product/LUMAPRO-Trade-Number-24PSB-21U505
>>
>> but longer. The above lamps are 1-7/64" long (28mm). The lamps I need to
>> replace measure 43mm.
>>
>> These things are OLD. The above Grainger bulb has a plastic wedge-shaped
>> base. The base of the lamps in this old equipment are wood.
>>
>> Any ideas on sources or even the proper size/type name?
>>
>
> T-2 bulbs measure 1-11/16" in total length. You are looking for 24C1
> Telephone and Indicator bulbs according to my old light bulb spec guide.
> They are rated as 0.06 - 085A, 1900 Footcandles, average cold resistance
> 33R, hours life = 5000.
>
> I might have those in my ancient parts stock if you can't find them
> elsewhere.
>
> At least you know what you are looking for now!
>
> John :-#)#
>

And here are some!

https://www.topbulb.com/light-bulbs/miniature-incandescent-bulbs/slide-base

Sjouke Burry

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Jun 16, 2018, 5:32:12 PM6/16/18

to

On 16-6-2018 2:12, Paul Hovnanian P.E. wrote:
> I need some to restore some old telco equipment. The bulbs are a slide base,
> 24V 2W incandescent, similar to these:
>
> https://www.grainger.com/product/LUMAPRO-Trade-Number-24PSB-21U505
>
> but longer. The above lamps are 1-7/64" long (28mm). The lamps I need to
> replace measure 43mm.
>
> These things are OLD. The above Grainger bulb has a plastic wedge-shaped
> base. The base of the lamps in this old equipment are wood.
>
> Any ideas on sources or even the proper size/type name?
>

Last time I had one of these fail, I soldered a led in
the metal part.