0-190-275V/6.3V toroid power transformer
British-made toroid for amplifiers up to approx 20W, Euro/US mains voltages
This toroid power transformer is made in England by a traditional and long-standing transformer winding company. Being toroidal in design, it has a major benefit over the conventional EI-style transformers – it radiates a significantly reduced electro-magnetic field, and that helps keep hum levels very low. It’s designed for use in a valve amp up to about 20W power output.
It has triple 0-110V + 0-110V + 0-20V primary windings and two secondary windings. The high voltage winding is 0-190-275V rated at 200mA. In a typical circuit, this will produce a maximum B+ of around 360V or so after smoothing. Or use the other taps to get a B+ of 110V or 260V. The heater supply secondary is a centre-tapped 6.3V rated at 3A. This makes it perfect for an amp using up to four 12AX7s (or equivalent) and two EL84/6V6/6L6s.
Dimensions & info
The toroid is 95mm in diameter and 42mm in height. It’s fixed with a single M5 bolt through a steel cupped washer on the topside. There are two large rubber washers (one to go between the steel washer and the transformer and the other to go between the transformer and your chassis). It’s secured in place with an M5 nut (included). This toroid mounts to the chassis with a single M5 hole; use a couple of 9.5mm grommets for the wires. See the second photo in the image gallery for the wiring diagram.