" I used to have a pal called OXO, Jim G6EQK, who used to use something of
a
similar device to the 3 dollar battery charger on TV tubes when they went
flat.


In fact this is how a lot of early 'live chassis' 405 line TVs worked,
except that they used a resistor in place of a light bulb.

73
Jeff

RMS wrote:


"Dr.Ace" wrote in message
...
3 Dollar lead acid Battery Charger
http://www.alpharubicon.com/elect/3dollarbattggn.htm

Ace, WH2T


Thank you!

RMS

Yuck!!

No voltage regulation at all, let alone the electric shock risk.

If you did connect a sulfated battery to this, the battery could easily drop
60V at normal charging current and it would get extremely hot, extremely
fast. I would not like to be near something full of hot sulfuric acid and
hydrogen and probably also a source of ignition in due course.

A modified PC power supply would be just as cheap and far safer.

Chris

Cheemag wrote:

On Sun, 22 Jul 2007 18:15:34 GMT, Al wrote:

In article ,
Mick wrote:

On Sun, 22 Jul 2007 10:33:37 +0000, Mike G4KFK wrote:

On Sat, 21 Jul 2007 00:12:59 +0000, RMS wrote:

"Dr.Ace" wrote in message
...
3 Dollar lead acid Battery Charger
http://www.alpharubicon.com/elect/3dollarbattggn.htm

Don't try this at homes with 240V AC, kiddies!


...even though it works if you pick a lower wattage bulb to keep the
charging current down. Not a good idea really. :-)

I've used series lamps a few times when testing "unknown" valve gear as
it helps keep the "holy smoke" inside the transformer box. Cheaper and
less noisy than fuses.

I use a variac and monitor the current as I turn it up.

All of this probably costs more than a cheap battery-charger
would !


Yes, they had some at Lidl a couple of months ago that were VERY cheap and
had regulated charging voltage, and looked like pretty good chargers.

Chris