Dead SureStart battery charger

[charliecambs]

Yep Newmarket were part of PYE/Philips we supplied transistors and PCB amplifiers and so on for the PYE/Philips record players.
We used to alloy the germanium transistors in furnaces ( in graphite holders) best bit was that a reject transistor could become an output stage temperature bias diode and as we were "world leaders" devices with different specifications from a process run were just allocated a new number and a datasheet created.
I had lots of devices (including new fangled silicon) when we closed the line many years ago but with a house move and the fact that the ready made stuff is so cheap means its pretty well all been scrapped.
In fact a couple of years after i retired early around 2017 the old factory was demolished.

 

[Barking Mat]

I have many dead battery chargers, I'd love to know how to diagnose.

They'll get binned soon, bet it's just an odd component.

Anyone ?

 

[zeppelin builder]

My old charger let out the magic smoke. I use it for electrolysis and think I may have shorted it out.

I know its worthless but it has memories for me and I would like to fix it.

Looking at it theres not much to it;

how about a 12 ac lighting transformer then connect up to the rectifier 5 amps output be ok

A transformer, an ammeter, a switch to change between 12v and 6v and a thing marked LT 213.

You can see the cooked transformer in the following pics;

So the question is, where can I find a replacement transformer. I've looked on RS but I dont know what I am looking at, only the £20-£50 they want to charge, so I'm not going there. I you've got any ideas please let me know.

I know its not really worth repairing, but it has sentimental value to me, so I would like to get it going again if posable.

 

[JohnH]

Thanks guys for the overwhelming response, and an especial thanks to those who have offered parts, but after some thought I have decided to not continue with this project. I dont know what I am doing and I know it will just go pear shaped, with me left smoking and twitching on the floor. Thanks for your time.

 

[pedrobedro]

I thought the way to do it was to use a battery between the charger and the tank so the charger is doing what it is made for.

 

[Alan Reynolds]

The OC71's only needed the black paint scraping off to become photo transistors. And hold them between your fingers and watch the leakage current soar as the temperature went up a few degrees. I have small box of Newmarket transistors removed from 1960's Pye Radio telephones; lots of numbers like "GET333" or similar.

Newmarket, well remembered. On the OC71, As Maurice Chevalier sang, ‘ah yes I remember it well.’ We had a German computer with an electronic pack constructed totally of germanium transistors, 100’s of them with a ferrite core store. It was called the Conti Wanderer, an electromechanical machine. Wanderer was certainly an apt description when it cane to the leakage.

 

[pawsnizzy]

Newmarket, well remembered. On the OC71, As Maurice Chevalier sang, ‘ah yes I remember it well.’ We had a German computer with an electronic pack constructed totally of germanium transistors, 100’s of them with a ferrite core store. It was called the Conti Wanderer, an electromechanical machine. Wanderer was certainly an apt description when it cane to the leakage.

You could buy unpainted OC71's, I think they were designated OCP71 - I'm sure, if I had a dig, I have some of both somewhere Not a hoarder, honest

 

[Ross365]

Some of the old transistors fetch a bit of money these days. I believe they are sought to build guitar "Wha Wha" boxes (a box on the floor you touch with your foot???) and there's a belief afoot (no pun intended ) that the effect is best accomplished using old circuits with Ge transistors. I may have to dig my OC71's out to help pay for the next delivery of heating oil. Nothing I ever built using Ge transistors worked. First thing of any significance that I built which worked was a two-valve SW radio.

 

[Seadog]

I've quite a lot of old semiconductors, including some crystal triodes. I'll dig them out one day, sell them, and buy a mansion