Hammond PWDF13243 Drake L4B Dual 3CX1200A7 Filament Transformer

PWDF13243 is a filament transformer for running two 3CX1200A7s in the Drake L4B. It is catalogued in Hammond's PWDAHL Series, the Peter W. Dahl collection of magnetics for amateur radio products, and is intended for experienced builders converting an L4B. The ordering table notes that this conversion requires extensive power supply and RF amp modifications.

The transformer provides two secondaries: S1 at 7.5 VCT @ 42A CCS and S2 at 22 VAC @ 1A CCS. The primary is 0-120/0-62-120 VAC, 60 Hz, single phase. As a 60 Hz part, the series advice applies: buyers who need 50 Hz should choose a part marked 50/60 Hz.

PWDF13243 is wound on an EI-150 x 2.5" 29GM6X core and listed as Style 4 on the series style sheet. The approximate weight is 12 lbs and the shipping weight is 12 lbs (5.44 kg). It is REACH compliant and RoHS compliant.

Like other PWDAHL designs, this unit is usually built to order one at a time, and Hammond recommends confirming availability by phone or e-mail. Identifiers are UPC 623980031866 and UNSPSC 39121301.

The dual primary taps (0-120 and 0-62-120 VAC) and the 42A center-tapped filament winding are the details to verify against your planned L4B power supply changes.