11-04-2013, 10:22 PM
http://sound.westhost.com/articles/buck-xfmr.htm
Figure 3 shows the bucking arrangement. The dot denotes the beginning of the winding: as you can see they are in opposite to each other. Disregard the Earth wire, it is not necessary unless you have the Earth wire. Also disregard the voltages shown - just know that on the left is your primary and on the right - secondary. I say 10-12V ransformer should work.
Choose one with the output current rating exceeding your radio's Mains current draw.
For instance if your raido is 50W total and so your primary draws roughly 0.5A choose the transformer with the secondary rated for at least 1A (the primary is not important - it automatically follows the power rating over the input voltage).
Figure 3 shows the bucking arrangement. The dot denotes the beginning of the winding: as you can see they are in opposite to each other. Disregard the Earth wire, it is not necessary unless you have the Earth wire. Also disregard the voltages shown - just know that on the left is your primary and on the right - secondary. I say 10-12V ransformer should work.
Choose one with the output current rating exceeding your radio's Mains current draw.
For instance if your raido is 50W total and so your primary draws roughly 0.5A choose the transformer with the secondary rated for at least 1A (the primary is not important - it automatically follows the power rating over the input voltage).