6 Volt 40mA dial lamps - UK Vintage Radio Repair and Restoration Discussion Forum

Alf Fisher · 3rd Jul 2022, 12:42 pm

Hi all,

I'm struggling to find a couple of these lamps.
I can find only one seller on ebay and he asking £99!
The radio isn't even worth that much!

These lamps are used in several models particularly Pye 445U and P93U that all use the valve lineup of UCH42, UF41, UBC41, UL41 and UY41.

I can get 50mA and 60mA so has anyone got a way enable either of these to be used?

Alf

JonSnell · 3rd Jul 2022, 1:53 pm

https://uk.rs-online.com/web/c/light...926,4291930118

robinshack · 3rd Jul 2022, 3:32 pm

Knowing the base fitting required would be a help.
I immediately imagine MES for a mains set.
Rob

G6Tanuki · 3rd Jul 2022, 5:12 pm

I'm thinking that 6 volt 40mA probably means they are the 'grain of wheat' wire-ended-micro-bulbs with flyleads that were used extensively as meter/dial-lamp illumination in 70s/80s radios/tuners etc.

peter_sol · 3rd Jul 2022, 5:27 pm

That Pye P93u. Is from 1955 so no grain of rice bulbs. Maybe the usual MES or equivalent.
They are listed in a Home radio catalogue of 1970.
The circuit shows resistors across them both so I should try the 50 MA ones.

Alf Fisher · 3rd Jul 2022, 6:00 pm

Sorry guys,
I missed the vital point that they are MES as Peter_sol has deduced.
I've done so much searching I've got brain fade.

Alf

Sideband · 3rd Jul 2022, 8:44 pm

6v 40mA were the old cycle dynamo lamps. You might find them on vintage cycle sites and suppliers.

Robsradio · 3rd Jul 2022, 9:22 pm

eBay have them, not cheap, but here is the item number: 110951791253

broadgage · 4th Jul 2022, 4:00 am

These are not the most common type of lamp but can still be found at reasonable prices.
Some old catalogues list two different types of 6 volt 40ma lamp, one is a pilot lamp and one a cycle dynamo tail lamp.

Used in cold war fallout shelters to provide minimal area lighting for DAYS from one set of batteries. A 996 lantern battery will run one of these for about 200 hours, or over a week. The rather feeble light is enough for safe movement in familiar surroundings with dark adapted eyes.

Alf Fisher · 4th Jul 2022, 6:32 am

Thanks Rob,
There was a strange effect with that number. Each time I entered it, I got a different lamp bulb. The first time it was 2.2v @ 0.25A, then next time 6volt @ 0.1A but the was a drop down option for 0.04A.
Thanks for the info Rob.
I'll give that one a try and see what I get.
Cheers, Alf

David G4EBT · 4th Jul 2022, 7:19 am

Don't know if you've seen this listing:

https://www.ebay.co.uk/itm/110851079...=&toolid=10050

Qty 5: 6V 40, 60 or 100 mA M.E.S. E10 Indicator Lamp Torch Bulb 0.04A 0.06A 0.1A

£4.95 + £2.95 'Buy It Now'.

(For one lot of five bulbs).

Hope that might help.

robinshack · 4th Jul 2022, 7:52 am

I just wonder if these are new production but made in China? Seems 1000s have been sold.
I had some in the past but just got rid in a bargain bag of assorted bulbs.
Seeing the prices, I must pay more attention!
Rob

broadgage · 4th Jul 2022, 2:53 pm

I rather doubt that these are still manufactured in view of what I suspect is very limited demand. Almost certainly old stock being sold.

As regards the ebay sellers claim to have sold thousands, I suspect that this is the TOTAL sales from a multi choice listing that includes large sales of far more popular types.

OTOH manufacture of miniature lamps is not that hard, and a small factory in China could probably make a small batch of a hundred or a few hundred if required. The current rating is very similar to that of a 120 volt, 5 watt nightlight bulb which is a popular type. So a lamp factory would have have stocks of suitable filament wire. Cutting it to length and mounting it in a standard small bulb, fitted with a standard small base is easy and similar to making other more popular miniature lamps.

Nickthedentist · 4th Jul 2022, 2:57 pm

Quote:

Originally Posted by JonSnell

https://uk.rs-online.com/web/c/light...926,4291930118

At that price, from a reputable seller, I'd get these as Jon suggests and do a base/holder transplant.

eBay specials, albeit with the correct base, may or may not be up to the job in terms of longevity; the three RS ones claim 2,000 to 20,000 hour life. Cycle and torch bulbs generally are designed to be more efficient in terms of light output per watt, but at the cost of shorter life (or so someone here told me once).

broadgage · 4th Jul 2022, 4:18 pm

Unless there is something unusually critical or demanding about the application basic ebay bulbs should be fine.

The smaller bulbs, about 11mm diameter were generally pilot lamps and the larger bulbs, about 15mm were generally cycle tail lamps.
The cycle lamps gave a very feeble light, and no light at all when stopped.

Torch bulbs had a typical life from a few hours to a few dozen hours.
Cycle lamps a few dozen hours, but very variable.
Motor vehicle headlamps often about a hundred hours, or a thousand hours for side lights. Dashboard indicators sometimes outlasted the vehicle.

Pilot lamps varied from a minimum of a thousand hours, up to many times that.

3rd Jul 2022, 12:42 pm	#1
Alf Fisher Hexode Join Date: Sep 2005 Location: Potton, Bedfordshire, UK. Posts: 262	6 Volt 40mA dial lamps Hi all, I'm struggling to find a couple of these lamps. I can find only one seller on ebay and he asking £99! The radio isn't even worth that much! These lamps are used in several models particularly Pye 445U and P93U that all use the valve lineup of UCH42, UF41, UBC41, UL41 and UY41. I can get 50mA and 60mA so has anyone got a way enable either of these to be used? Alf

3rd Jul 2022, 1:53 pm	#2
JonSnell Hexode Join Date: Oct 2019 Location: Weymouth, Dorset, UK. Posts: 292	Re: 6 Volt 40mA dial lamps https://uk.rs-online.com/web/c/light...926,4291930118 __________________ Valve equipment repairs since 1968 www.jonsnell.co.uk

3rd Jul 2022, 3:32 pm	#3
robinshack Octode Join Date: Jun 2010 Location: Spalding, Peterborough, Cambridgeshire, UK. Posts: 1,919	Re: 6 Volt 40mA dial lamps Knowing the base fitting required would be a help. I immediately imagine MES for a mains set. Rob __________________ I am also interested in and collect 00 model railway. My avatar is Bruiser, he has cauliflower ears!

3rd Jul 2022, 5:12 pm	#4
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 11,391	Re: 6 Volt 40mA dial lamps I'm thinking that 6 volt 40mA probably means they are the 'grain of wheat' wire-ended-micro-bulbs with flyleads that were used extensively as meter/dial-lamp illumination in 70s/80s radios/tuners etc. __________________ "The future's so bright I gotta wear shades". --Timbuk3

3rd Jul 2022, 5:27 pm	#5
peter_sol Octode Join Date: Aug 2003 Location: Welwyn Garden City, Herts. UK. Posts: 1,775	Re: 6 Volt 40mA dial lamps That Pye P93u. Is from 1955 so no grain of rice bulbs. Maybe the usual MES or equivalent. They are listed in a Home radio catalogue of 1970. The circuit shows resistors across them both so I should try the 50 MA ones. Last edited by Cobaltblue; 3rd Jul 2022 at 9:27 pm. Reason: Edited per OP request

3rd Jul 2022, 6:00 pm	#6
Alf Fisher Hexode Join Date: Sep 2005 Location: Potton, Bedfordshire, UK. Posts: 262	Re: 6 Volt 40mA dial lamps Sorry guys, I missed the vital point that they are MES as Peter_sol has deduced. I've done so much searching I've got brain fade. Alf

3rd Jul 2022, 8:44 pm	#7
Sideband Dekatron Join Date: Oct 2003 Location: Croydon, Surrey, UK. Posts: 6,819	Re: 6 Volt 40mA dial lamps 6v 40mA were the old cycle dynamo lamps. You might find them on vintage cycle sites and suppliers. __________________ On Spike Milligan's headstone......I told you I was ill...

3rd Jul 2022, 9:22 pm	#8
Robsradio Hexode Join Date: Nov 2010 Location: Isle of Wight, UK. Posts: 348	Re: 6 Volt 40mA dial lamps eBay have them, not cheap, but here is the item number: 110951791253

4th Jul 2022, 4:00 am	#9
broadgage Octode Join Date: Jan 2010 Location: North Somerset, UK. Posts: 1,995	Re: 6 Volt 40mA dial lamps These are not the most common type of lamp but can still be found at reasonable prices. Some old catalogues list two different types of 6 volt 40ma lamp, one is a pilot lamp and one a cycle dynamo tail lamp. Used in cold war fallout shelters to provide minimal area lighting for DAYS from one set of batteries. A 996 lantern battery will run one of these for about 200 hours, or over a week. The rather feeble light is enough for safe movement in familiar surroundings with dark adapted eyes.

4th Jul 2022, 6:32 am	#10
Alf Fisher Hexode Join Date: Sep 2005 Location: Potton, Bedfordshire, UK. Posts: 262	Re: 6 Volt 40mA dial lamps Thanks Rob, There was a strange effect with that number. Each time I entered it, I got a different lamp bulb. The first time it was 2.2v @ 0.25A, then next time 6volt @ 0.1A but the was a drop down option for 0.04A. Thanks for the info Rob. I'll give that one a try and see what I get. Cheers, Alf

4th Jul 2022, 7:19 am	#11
David G4EBT Dekatron Join Date: Feb 2003 Location: Cottingham, East Yorkshire, UK. Posts: 4,917	Re: 6 Volt 40mA dial lamps Don't know if you've seen this listing: https://www.ebay.co.uk/itm/110851079...=&toolid=10050 Qty 5: 6V 40, 60 or 100 mA M.E.S. E10 Indicator Lamp Torch Bulb 0.04A 0.06A 0.1A £4.95 + £2.95 'Buy It Now'. (For one lot of five bulbs). Hope that might help. __________________ David. BVWS Member. G-QRP Club member 1339.

4th Jul 2022, 7:52 am	#12
robinshack Octode Join Date: Jun 2010 Location: Spalding, Peterborough, Cambridgeshire, UK. Posts: 1,919	Re: 6 Volt 40mA dial lamps I just wonder if these are new production but made in China? Seems 1000s have been sold. I had some in the past but just got rid in a bargain bag of assorted bulbs. Seeing the prices, I must pay more attention! Rob __________________ I am also interested in and collect 00 model railway. My avatar is Bruiser, he has cauliflower ears!

4th Jul 2022, 2:53 pm	#13
broadgage Octode Join Date: Jan 2010 Location: North Somerset, UK. Posts: 1,995	Re: 6 Volt 40mA dial lamps I rather doubt that these are still manufactured in view of what I suspect is very limited demand. Almost certainly old stock being sold. As regards the ebay sellers claim to have sold thousands, I suspect that this is the TOTAL sales from a multi choice listing that includes large sales of far more popular types. OTOH manufacture of miniature lamps is not that hard, and a small factory in China could probably make a small batch of a hundred or a few hundred if required. The current rating is very similar to that of a 120 volt, 5 watt nightlight bulb which is a popular type. So a lamp factory would have have stocks of suitable filament wire. Cutting it to length and mounting it in a standard small bulb, fitted with a standard small base is easy and similar to making other more popular miniature lamps.

4th Jul 2022, 4:18 pm	#15
broadgage Octode Join Date: Jan 2010 Location: North Somerset, UK. Posts: 1,995	Re: 6 Volt 40mA dial lamps Unless there is something unusually critical or demanding about the application basic ebay bulbs should be fine. The smaller bulbs, about 11mm diameter were generally pilot lamps and the larger bulbs, about 15mm were generally cycle tail lamps. The cycle lamps gave a very feeble light, and no light at all when stopped. Torch bulbs had a typical life from a few hours to a few dozen hours. Cycle lamps a few dozen hours, but very variable. Motor vehicle headlamps often about a hundred hours, or a thousand hours for side lights. Dashboard indicators sometimes outlasted the vehicle. Pilot lamps varied from a minimum of a thousand hours, up to many times that.