UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - AR-88 Power supply current capability?

turretslug · 29th Dec 2018, 10:24 pm

These transformers give an initial impression of being quite big and heavy- but much of that comes from being potted into an outer steel can, as the others say the HT current rating is actually quite modest. Furthermore, the original design uses a relatively high impedance rectifier (5Y3GT) feeding just 4uF reservoir followed by a 400 ohm first choke, so it will have been specified around relatively modest amplitude charging pulse capability. Don't count on making anyone's ears bleed with it!

The SC number signifies US Signal Corps approval but I don't know what the number itself signifies, whether an inspector, a depot or a specification.

29th Dec 2018, 10:24 pm	#5
turretslug Dekatron Join Date: Nov 2011 Location: Surrey, UK. Posts: 4,398	Re: AR-88 Power supply current capability? These transformers give an initial impression of being quite big and heavy- but much of that comes from being potted into an outer steel can, as the others say the HT current rating is actually quite modest. Furthermore, the original design uses a relatively high impedance rectifier (5Y3GT) feeding just 4uF reservoir followed by a 400 ohm first choke, so it will have been specified around relatively modest amplitude charging pulse capability. Don't count on making anyone's ears bleed with it! The SC number signifies US Signal Corps approval but I don't know what the number itself signifies, whether an inspector, a depot or a specification.