UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post

G6Tanuki · 26th Aug 2019, 6:57 pm

Hi Chris,

It's working as an auto-transformer giving a 2:1 audio-signal step-up ratio, but it also provides a DC path for the bias voltage to get from the GB-battery to the valve-grid.

There were various different ways of doing transformer/choke-coupling over the years, must admit I've not come across it being done the way you describe but I can understand the logic of it.

26th Aug 2019, 6:57 pm	#4
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 13,996	Re: Interstage Audio coupling transformer Hi Chris, It's working as an auto-transformer giving a 2:1 audio-signal step-up ratio, but it also provides a DC path for the bias voltage to get from the GB-battery to the valve-grid. There were various different ways of doing transformer/choke-coupling over the years, must admit I've not come across it being done the way you describe but I can understand the logic of it.