Making of an HT battery

Having got 90 AA cells from Halfords it was time to make the HT battery, because I am not quite sure of the volts required it has taps at every 1.5V at the bottom for 15V and 15V taps down from 135V at the top.

Pictures...

First, the cells as from Halfords.
Second, cells unwrapped and the plasticard box to fit them in
Third, cells in the box, stuck together but not to the box itself.
Fourth, tops of cells wired together.
Fifth, bottom of cells wired together.

More pics to come...

Sixth, you neet to connect to the outside world, little brass tubes to fit wander plugs.
Seventh, insulate the tubes with paper, also makes them fit in the gaps
And eighth, the tubes poking through the lid, voltage taps are up to you.

Now all I need is a pretty cover.

[AlanBeckett]

merlin,
Are you going to add some fusing or current limiting? Battery sets tend to only take a few mA but that could supply some serious current if anything goes wrong
Alan

[paulsherwin]

You could also give yourself quite a belt.

[Sean Williams]

Thats a nice lethal looking battery! - I like it!

Fusing will be in the set, the classic 6V 60mA bulb I think. I did get tickled a couple of times handling the block while attaching the 'sockets'. Suppose I best not use water based glue to fix the cover on, not with both hands anyway.

There is quite a lot of energy in this, not to be treated with complacency. If you know the hazzards it is safe.

Originally Posted by Sean Williams

Thats a nice lethal looking battery! - I like it!

Yup, fifteen quids worth of death (if missused), soon you will be only able to buy 16 cells at a time like paracetamol and asprins.

[ppppenguin]

Originally Posted by Sean Williams

Thats a nice lethal looking battery! - I like it!

Reminds me of something I saw at BBC Research back in the 1970s. A nice smooth DC supply, several hundred volts, was needed for a photomultiplier. This was in the days you could still get HT batteries. There were 10 B126 90V batteries in the box. 900V! A lot cheaper than a Brandeburg or similar high quality stabilised EHT PSU at the time.

[mickjjo]

Excellent job! Prewar HT batteries were made in much the same way, It would be safer to recess those tubes below the surface to avoid accidental contact with fingers and metal objects though.

Regards, Mick.

I left them a bit proud so I can puncture the cover using a small hammer, that will also recess them as a bonus if hit hard enough (didn't think of that, thanks).

But what to call it, the name on the pretty cover, PertinAxe of Death?

Too morbid, suggestions please.

[EF80TVVALVE]

I think I will have a go at making one of these for that civilian radio. I think I will wear a few pairs of rubber gloves, just for reassurance. Thanks for making the thread, I do now have a better understanding of making a battery. (I think soon I will be making more than I need )

...needed for a photomultiplier... There were 10 B126 90V batteries in the box. 900V!

A wonderfully simple solution. And you could tap down the chain without a wasteful resistor ladder.

EFT80VVALVE,

The contacts on the cells are nickel plated, a quick going over with emery paper makes them easier to solder, as does using Fluxite. Use a fairly big soldering iron and wire the individual chains first before connecting the lot up as this leaves it at a lower voltage until the last connexions are made.

Got the tube from a model shop along with the plasticard.

[mickjjo]

Attached is an advert from Popular Wireless magazine, Feb 1934, for "Grosvenor" HT batteries. Allowing for inflation, yours may well work out cheaper to make.

Regards, Mick.

[TuningIndicator]

Great work, MM. Look forward to seeing the artwork; super-sized Ever-Ready logo maybe?
I dare say Halfords were on to Special Branch after you left; thinking you were up to no good.
That bottle of Liquid Poly takes me back 30 odd years.........

yours may well work out cheaper to make.

I did some ballpark calculations when making the battery for my P17B, about one half the cost and twice the life.

[Peter.N.]

Why don't you got to your local radio shop for a 120 volt 'Winner' Our local cinema used batteries about the size of yours for back up during power cuts just after the war.

Peter

[TuningIndicator]

^^ I don't know about 'Winner', I think 'Killer' would be more appropriate.

That bottle of Liquid Poly takes me back 30 odd years...

That bottle has been refilled a few times, I have nearly a gallon of MEK left.

Back to the name, I have already done the Ethelred GB battery (see my very first post here) could be the Revolt HT (given the current situation in the middle east).