Albert wrote in message . ..

Clearly, this was a 12v supply and not a 13.8v supply. The actual
output current ratings are not known, the only hint is that the
original meter was a 25 amp meter.

The transformer is much larger than 100 va and is actually larger than
a 200 va unit (based on core size). When I tore down the rest of the
assembly, I found more shaky stuff including sockets for the
transistors that were soldered, several etch cuts and lifted run on
the PCB, meter shunt was missing (probably discarded when the original
pcb was replaced). In other words, it probably needs a complete
redesign rather than using any of the original parts and pc boards.

I ran LTC's power supply design software and it came up with a 13.8
volt output switching supply that will supply 14A with the existing
power transformer. It uses the LTC1775 switching regulator, 2 X
Si4410DY mosfets, an 11 uH inductor and a couple of 1N5818 schottky
diodes. The supply itself (not including transformer losses and
rectifier losses) provides 98 percent efficiency at 14A output.

So, I'm considering building up this switching supply.

I need suggestions for a schottkey bridge rectifier that will handle
20A or more. I find the diodes themselves are readily available, but
I'd like to have a bridge assembly if possible.

Any suggestions??


Of course I've not seen the unit but it strikes me that sorting those
bugs out may be quicker than a complete rebuild - they dont sound like
hard to fix issues.

The main plus with that is you get out the full amount of oomph that
your power TF is capable of giving. If its got a 25A meter on it,
chances are it can give at least 20A, and probably 25A. Other plus is
its less work.


Regards, NT