Live speaker connections - UK Vintage Radio Repair and Restoration Discussion Forum

Biggles · 21st Jun 2014, 5:33 pm

Hi all, most of you are probably already aware but I thought it might be worth a mention that on certain AC/DC sets such as the Stella ST113U I am working on at present have no audio output transformer and as a result the (high impedance) speaker connections are at full HT potential. It does mention this in the service info but I thought it prudent to point out this "hidden" danger for those who may assume that the speaker is at low potential. This presents both an electric shock hazard and also a test equipment connection hazard.
Alan.

camtechman · 21st Jun 2014, 6:08 pm

I remember finding out the hazzard of live speaker connections when I was 12 (55 years ago!) when I tried to connect the "Radio In" socket on my R2R, via a wire from the speaker of Mum & Dad's old radiogram.

When I came round, lump on head, I the found out the problem it had also caused to my R2R !

21st Jun 2014, 5:33 pm	#1
Biggles Rest in Peace Join Date: Feb 2004 Location: Hexham, Northumberland, UK. Posts: 2,234	Live speaker connections Hi all, most of you are probably already aware but I thought it might be worth a mention that on certain AC/DC sets such as the Stella ST113U I am working on at present have no audio output transformer and as a result the (high impedance) speaker connections are at full HT potential. It does mention this in the service info but I thought it prudent to point out this "hidden" danger for those who may assume that the speaker is at low potential. This presents both an electric shock hazard and also a test equipment connection hazard. Alan.

21st Jun 2014, 6:08 pm	#2
camtechman Nonode Join Date: Jan 2008 Location: Milton Keynes, Bucks. UK. Posts: 2,552	Re: Live speaker connections I remember finding out the hazzard of live speaker connections when I was 12 (55 years ago!) when I tried to connect the "Radio In" socket on my R2R, via a wire from the speaker of Mum & Dad's old radiogram. When I came round, lump on head, I the found out the problem it had also caused to my R2R ! __________________ When I die, please don't let my Wife sell my collection for the amount I told her I paid for it!