Hammond PWDP13224 National HRO-60 Receiver Power Transformer

The PWDP13224 is a power transformer for the National HRO-60 (R). The ordering table describes it plainly as not an exact replacement but one that will fit in, which makes it a practical option for restorers of the HRO-60. It belongs to the PWDAHL series of Peter W Dahl Transformers for amateur radio products.

The primary accepts 115/230 VAC at 60 Hz, single phase. Three secondaries are supplied, each rated CCS: S1 at 550 VCT and 200 mA, S2 at 5.0 VAC and 3 A, and S3, a tapped 0-6.3-13.3 VAC winding rated 6 A.

The core is an EI-150 x 2 lamination, built in Style 5 on the transformer style sheet. Approximate weight is 10 lbs, with a shipping weight of 10 lbs (4.54 kg). The part is RoHS and REACH compliant.

The tapped S3 winding (0-6.3-13.3 VAC at 6 A) gives two voltages from one winding, and the 115/230 VAC primary rating lets the PWDP13224 be connected for either supply voltage at 60 Hz.

Since the PWDP13224 is listed for 60 Hz, those on 50 Hz supplies should heed the series note to look for 50/60 Hz parts. Dahl transformers are usually built to order, so confirming availability first is recommended.