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Old 24th Mar 2010, 1:09 pm   #3
David G4EBT
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Join Date: Feb 2003
Location: Cottingham, East Yorkshire, UK.
Posts: 5,737
Default Re: DIY Number 8 Battery Adaptor

Hi David,

Thanks for reading my posting and for your comments.

Re the PP6, I think that may have been discussed on the forum before. You can get them, (just as you can the No 8) but at a price. EG, here:

http://www.cellpacksolutions.com/Sea...eet.asp?ID=PP6

Like many who grew up in the 1940s, I have fond memories of the No 8 battery. Small torches which used the No 8 seemed to be popular back then - maybe being smaller even than U11 batteries, they were cheap to buy in the war years, (when you could get batteries that is!). The downside is that they didn't last long.

My bedroom was on the top floor of a three story house and wasn't wired for electricity, so my little torch was a constant companion to extend reading hours beyond bedtime beneath the blanket!

I also had a penlight torch - I think it was made by Lucas. It had a metal case and clipped into the top pocket. When you wanted to use it, you pressed the clip against the barrel of the case which acted as a switch. It took a couple of what are now called AA cells.

I've made another No 8 battery adapator a bit simpler than the one I mentioned in my first post, this time using two LR1 cells, which can be had for under a pound the pair, but are 1 A/Hr compared to a 3V lithium battery, which is 1.6A/Hr. For occasional use as in my little signal injector, 1A/Hr would be fine.

This 'Mk2' adaptor consists of a spacer to fit between the two LR1 cells to make up the length of 74mm (the length of a No 8), a tube made from rolled up card, rolled around a ballpoint pen case of the right diam for the batteries to be a sliding fit, and a length of 20mm plastic conduit as before.

The paper tube is pushed inside the plastic conduit with a dab of glue to keep it in place.

If desired, more card and a replica label could be glued to the outside of the conduit to make it up to the diameter of a No 8- 22mm. Or a length of 22mm copper pumbling pipe could be slid over the conduit to make up the diameter, but I'm not personally concered about making an exact replica - only about functionlity.

I cut the spacer from a piece of aluminium rod, about 11mm diam, (same as the cells), but a piece of metal cut from a bolt or whatever is to hand would do just as well.

The pic is self explanatory.

Hope it's of interest.

David,
G4EBT
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