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Recommendations for new power transformer

F

fmjunkie

Member
Hey there gang. I recently picked up a pair of Arte Forma 300B monoblocks and one has a shorted power transformer. The tranny is 760V (380-0-380) at 300mA center tapped, 6.3V center tap (3.15-0-3.15) at 3A and two 5V @ 4A (see photos). I'm having trouble finding an exact match. A friend recommended the Hammond 300BX, but the 5V taps are only 1.2A and 3A. Any recommendations are welcome. Thanks.

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I always ask this when I see threads like this but just out of curiosity, how do you know the power transformer is bad? Is it shorted all by itself with absolutely nothing connected to the secondary?

I don't know your level of expertise but usually when there is a bad power transformer thread, its almost always a shorted can capacitor. Have you checked all of these things first?

Have you checked it with a meter?
 
Check out the Raphaelite power transformers on a popular auction site. Some models come very close to what you need.
 
century tek said:
I always ask this when I see threads like this but just out of curiosity, how do you know the power transformer is bad? Is it shorted all by itself with absolutely nothing connected to the secondary?

I don't know your level of expertise but usually when there is a bad power transformer thread, its almost always a shorted can capacitor. Have you checked all of these things first?

Have you checked it with a meter?
Click to expand...

Thanks Century Tek. I'm not an expert, but have been a hobbyist for about 10 years or so. I'm not a newbie but am still learning. Anyhow, I did disconnect all secondaries and powered on slowly with my variac. The power fuse blows immediately. A meter across the primary windings show continuity. Checked the power switch just in case and it's good.
 
I'd think Heyboer may be able to rewind it or clone it. Provided they're not closed in the current situation, that is.
 
There looks to be room to put aux heater transformers underneath. This would let you mount a plate trans where the OE one now rests. Or use a combination plate and heater, and supplement with an aux or two as needed. This way you can focus on getting a closer high voltage winding.
cheers,
Douglas
 
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