AD28 Batteries

[Old Sparky]

Several EBay sellers and others stock the 4.5v AD28 Batteries used in a wide variety of items, including some vintage transistor radios such as the Perdio 'Caralux'.  I purchased two for under £10 for one of these radios.  The batteries are branded 'Eveready', and consist of 3 x 1.5v  zinc carboncells wired in series.  When I fitted them to the radio, which I'd recently repaired and knew to be working,there was no output!  On inspections the batteries were easily openable, and I found that, in one, a wire linking one outer cell's negative to the Positive button on the centre cell wasn't connected.  Resoldering the wire corrected the fault, which saved me having to return the battery to the supplier.  Pictures of the batteries involved are to be gfound on EBay.  They all appear to be the same type, so others may suffer from this problem.  

[ppppenguin]

And when they fail it should be easy enough to open them up and stick 3x alkaline cells inside. Even AA cells might give long enough life.

[Terry]

Rather than paying close on £5 each for replacement batteries, wouldn't it be simpler and much cheaper to replace the dry cells in the old AD28 packaging with three alkaline cells?

All you would need is a couple of AA cell holders as a one-off investment - and, of course, you will be enable to ensure that they are correctly wired! - then fill them with AA alkaline cells from Poundland which will cost you the grand sum of £1 for six.

I don't know how the capacity of an alkaline AA compares with one of the original zinc carbon cells but even if you have to replace them twice as often, you are still getting two AD28 replacements for £1!

EDIT: Ah, I see Jeffrey has had the same idea!

[Old Sparky]

Good Idea from both Jeffrey and Terry. Why didn't I think of that?

[Refugee]

I used rechargeable batteries in my Pigmy 501 in two 3 cell holders with fly-leads and tabs.