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General Vintage Technology Discussions For general discussions about vintage radio and other vintage electronics etc. |
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1st Nov 2020, 10:21 am | #1 |
Nonode
Join Date: Dec 2012
Location: Bocking, near Braintree, Essex, UK.
Posts: 2,071
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Dial lamps
Is there any conversion for those 6.5v 0.3A dial lamps to bright LED ones as the standard dial lamps are getting pretty hard to buy in most shops.
Can any member tell me please,, I have been suggested to try e bay Ken |
1st Nov 2020, 10:45 am | #3 |
Moderator
Join Date: Dec 2010
Location: Exeter, Devon and Poole, Dorset UK.
Posts: 6,863
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Re: dial lamps
Hi Ken
Not having too much trouble getting 6V bulbs as yet. There are tons as Donald has shown. If you want to go LED you could make your own a bit fiddly but do-able. I saw these but they are designed for DC you would need to add a diode to the lamp holder or modify them https://www.ebay.co.uk/itm/3V-6V-DC-....c100005.m1851 I am sure a search would bring up more Cheers Mike T
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Invisible airwaves crackle with life or at least they used to Mike T BVWS member. www.cossor.co.uk Last edited by Cobaltblue; 1st Nov 2020 at 10:46 am. Reason: Partial cross with DonaldStott |
1st Nov 2020, 11:34 am | #4 |
Nonode
Join Date: Oct 2010
Location: Tintinara, South Australia, Australia
Posts: 2,339
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Re: dial lamps
RS also do direct LED replacements - search for 'LED Indicator Lamps'
Might want to sort the search results by price, the first ones that come up will probably give you heart failure. |
1st Nov 2020, 12:24 pm | #5 |
Octode
Join Date: Mar 2011
Location: Sheffield, South Yorkshire, UK.
Posts: 1,453
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Re: dial lamps
What I've found is that the lamps which are widely available don't last long. They are really torch bulbs made to be as bright as possible for a given current at the expense of longevity. I've found it best to add a 2.2Ω resistor in series with them.
Homebrew LEDs have the added challenge of the light coming out in a relatively narrow beam. The RS one's seem to be deliberately made to throw all their light forwards whereas some radios need it coming from the side of the lamp. These are the 'proper' ones: https://uk.rs-online.com/web/p/filam...lamps/0104806/ Last edited by ThePillenwerfer; 1st Nov 2020 at 12:39 pm. Reason: Link added. |
1st Nov 2020, 3:07 pm | #6 |
Nonode
Join Date: Dec 2012
Location: Bocking, near Braintree, Essex, UK.
Posts: 2,071
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Re: Dial lamps
Thanks everyone for their contribution, it looks like RS will be the ones I choose.
Regards Ken |
1st Nov 2020, 4:01 pm | #7 |
Nonode
Join Date: Jan 2010
Location: North Somerset, UK.
Posts: 2,129
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Re: Dial lamps
6 volt dial lamps are still readily available, and probably will be available for decades yet as they are one of the most popular types.
LED alternatives exist but take care. If the lamps are part of a parallel circuit, then an LED alternative should be fine. The new LED pilot lamp does not "know" if the 6 volts is from a valve heater transformer or from some other source. If however the pilot lamps are part of a SERIES circuit, then LEDs are unlikely to work and might even be dangerous. Torch bulbs and pilot lamps are very different products and it is regrettable that an increasing number of suppliers don't seem to know or to care about the difference. Torch bulbs are designed to obtain the most light from the limited and very expensive energy in torch batteries. Design life varies from a few hours up to a few dozen hours. Pilot lamps are intended to give a long and reliable life in applications when energy is cheap and plentiful, as in the case of mains supplies, vehicle electrical systems and large accumulators. The minimum life is often 1000 hours, and much longer lifetimes are common. In a previous job I used to get through well over a thousand 6 volt pilot lamps a year, and several hundred a year of other types. I favoured either RS own brand or Lucas lamps. The Lucas lamps are primarily intended for dashboard indicators in vehicles, and are called "6 volt" by convention, but are actually designed for about 7 volts, this being the average voltage when a 6 volt vehicle battery is on charge. |