Not balancing the magnetomotive forces is never a good idea, especially, when designing an amplifier's mains power transformer. If the primary is not distributed on the two sides of the core, this will lead to a lot of magnetic leakages, which link with the amplifier's highly sensitive input circuitry. To minimize magnetic flux leakages, you have to avoid sharp edges in the design of the iron core, and to distribute all coils evenly over the entire magnetic core. I strongly suggest readers to consider these before attempting to build a transformer like this. Magnetic leakages lead to very hard to rectify hum issues that ruin an amplifier's performance. An alternative way to mimic a toroidal core is to use the stator of a motor. Given a sufficiently thick stator core, one can saw off the inner sides where the stator coils are wound.
Obviously you have used the seond bobbin to hold the core together, you could press holes at the end of I's that would make neat and clean transformer along with mounting nuts and bolts.
The thick wire which you have used here as Secondary is LV which used near to core not outer of the core and like wise the wire you have used as primary is HV so it should be outside by doing this Flux leakage is minimum and TAPPINGS can be taken easily!
Why at the end, when you connected the two coils in series, bulb didn't light up? And if secondary is open, and you connect bulb in series with primary and if bulb lights up, does it mean the primary winding is good or it means it's bad?
स्माल साइज़ वेल पॉवर फैक्टर (crgo)कोर आई टाइप | क्रॉस सेक्शन एरिया example १०x १० = १०० लम रूल्स ४२ /१०० =०.४२= १ वोल्ट = ०.४२ turns ac २२० x ०.४२ =९२.४ turns अति
Transformers of this type (U-I) suck! They are are very lossy and consequently have poor voltage regulation. Toroids are much better nut are also more expensive.
