Harry Bloomfield was thinking very hard :
on 13/09/2007, supposed :
Hi all,

Just an academic question.

What used to be used in Car Battery charger to convert the AC - DC
before silicon diodes/bridge rectifiers came along?

And did they do full rectification or just half wave?

Selenium rectifiers - easy to spot by the large metal cooling fins. Any over
heating in the selenium and they would be easily damaged. Once you have smelt
one failing, you could instantly recognise it the next time. I think most
were full wave, either using the two diode method or four.

smelt = smelled :-(

There is an example of one on Ebay...

http://cgi.ebay.com/ebaymotors/Honda...spagenameZWD2V

--

Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk