From Russia with love...

[Professor]

Just another one LM3886

[digi01]

very neat front panel

[Professor]

inside...

[wes-ninja250]

What's with the extra wires on the transformer?

Wes

[Panelhead]

That is a simple trick to get a low voltage, low power tap. Just wrap enough to get whatever voltage you need.

George

[digi01]

accomplished building,Russia diyer.you have impressed me

Zang

[wes-ninja250]

Thanks, I had thought it might be a low-voltage tap, but couldn't see another bridge rectifier on there anywhere.

Any idea how the four wires are wired up? in series to make one really long wire, then the "ends" of the really long wire give us AC?

I had actually considered doing something like this to get ~8VAC 0.3A in the amp I'm building.. any idea how to figure out if this is possible on my toroid? (specifically -- how do I figure out current capacity? Overload and look for sag?) I was actually getting ready to just use a 9V battery.

Wes

[Panelhead]

Originally posted by wes-ninja250
Thanks, I had thought it might be a low-voltage tap, but couldn't see another bridge rectifier on there anywhere.

Any idea how the four wires are wired up? in series to make one really long wire, then the "ends" of the really long wire give us AC?

I had actually considered doing something like this to get ~8VAC 0.3A in the amp I'm building.. any idea how to figure out if this is possible on my toroid? (specifically -- how do I figure out current capacity? Overload and look for sag?) I was actually getting ready to just use a 9V battery.

Wes

This may not be a LED supply. Normally that only requires 3 - 4 wraps. Maybe it powers a higher voltage LED, most here are 3.5 volts. And guess that depends on the transformer too.
300 ma sounds a little tough, most I have seen are 10 - 20 ma circuits. The coupling on top of the normal windings is not so good, the amount of current will be limited.

George


George

[Professor]

Originally posted by Panelhead
That is a simple trick to get a low voltage, low power tap. Just wrap enough to get whatever voltage you need.

George

Beforehand I am sorry for the English.

You are completely right, I had to make such winding to receive 12V for a feed(meal) of low-voltage circuits. Any other variants simply were not located in the case.