Hammond 373EX 311VA 650V C.T. Plate & Filament Power Transformer

The 373EX is a 311 VA high voltage (plate) and filament transformer from the 300 Series, rated 650V C.T. @ 345ma. on its A.C. high voltage secondary. It is intended for designers, builders and repair technicians working on vacuum tube equipment who need a plate supply, two filament supplies and a bias source from one universal-primary transformer.

The 373EX delivers 650V C.T. at 345 mA from a 311 VA rating, with heavy 5V C.T. 6A and 6.3V C.T. 9A filament windings; the manufacturer's short description lists 342VA.

The universal primary accepts 100, 110, 120, 200, 220, 230 and 240 VAC at 50/60 Hz. Units are designed to operate with BOTH primary windings engaged, so follow the manufacturer's primary wiring information when connecting it. The secondary provides a 50 VAC bias tap taken from the high voltage secondary with the C.T. grounded, and the unit can be run full wave bridge or full wave C.T.

Construction includes a Faraday copper primary shield, an electrostatic shield internally grounded to the end bell that reduces capacitive coupling from the primary, and concentric windings for low stray field and low noise. Each unit is highpot tested at 2,000 VAC and finished in black powder paint to match the 1650 series of output transformers.

• Mounting: vertical ("X") mounting
• Shipping weight: 11.5 lbs (5.22 kg)
• CSA certified (209651); RoHS and REACH compliant
• UPC 623980252773

It is built on dimension reference X23 in the series specification sheet. The 300 Series is an upgrade from the entire 200 Series range of units.