Tag: green

The Bardic lamp was introduced into the British railway system by the Bardic company of Southampton sometime around 1962. Just about everyone who has worked on the railway since then in a trackside role was given one as a personal issue.

Fast forward to today and new plastic LED lamps are being issued, however they don’t have the appeal of the old lamps, they break easy and the lens colours are not true Red, Green and Amber that they should be. The old style Bardic lamp is still in use many of which are still being used today. I still have the original one issued to me back in 1992.

This post is going to cover a basic power conversion for these lamps that will hopefully result in them being used for many more years.

The fundamental issue with these lamps is that they use an old Mercury cadmium battery that accepts two pins that insert into the top of the cell. Even though these batteries used to be available for a reasonable amount of money, nowadays it is unethical to purchase these batteries due to their construction they have in theory been banned, so they are no longer manufactured. They can though still be purchased via the web at extremely inflated prices, however they can’t guarantee that they would still work – so you take your chances.

With this simple conversion we can extend the life of this unit and save it from being cast aside as waste. The conversion is very cheap, uses std “D” cell batteries and can be converted by anyone – even me. Kits to do this can be purchased for around £10 (GBP) on line, but this one should not cost more than £2 (GBP) even less if you have the parts as spares.

There are two ways of doing this conversion, the way the kit works is to use a couple of electrical “Choc bloc” adaptors to connect to the male pins of the AD28 connector (I’ve used that example on this page). The cheaper option is simply to have a 3 cell “D” type battery holder, cut the old AD28 connector off, solder the two wires together and use some heat shrink to cover the solder joints. Simple.

This really is a ten minute job that increases the lifespan by years.

The conversion is completed with the D cell battery holder being stuck to the base with some hot glue. I’ve also put some on the chocolate bloc connectors for some extra strength and protection from the damp.

We recycle these batteries at work with a company that we have connections with, I also take spent batteries to the local supermarket that also recycles. The old AD28 batteries go to a specialist company for recycling/disposal.

Pretty basic and I now have a constant supply of these coming into us from our locations throughout the East Midlands awaiting conversion. We now do the basic simple conversion with our own stock and I think we have the conversion cost down to about £1.80 GBP per unit. A very cost effective simple conversion that will keep a 50+ year old lamp going for a few more years.