190-0-190V toroid power transformer
British-made toroid for amplifiers up to approx 10W, Worldwide 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 the Amp N5X amp kit and can run an octal power valve and up to 3 preamp valves.
It has a worldwide primary: 100V, 120V, 220V, 230V and 240V. There are two secondary windings. The high voltage winding is 190-0-190V rated at 80mA. In a typical circuit, this will produce a maximum B+ of around 250V or so after smoothing. The heater supply secondary is a centre-tapped 6.3V rated at 2.5A. This makes it perfect for an amp using up to four 12AX7s (or equivalent) and an EL84/6V6/6L6.
Dimensions & info
The toroid is 78mm in diameter and 54mm in height (including the fitting disks). 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.