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previous: Dave Stork I feel the need to pose my earlier ... -- 3/24/1999 9:40 AM View Thread

Re: U.L certification

3/24/1999 7:59 PM
Re: U.L certification
Here's a UL site if anyone is interested. Seems they've been around for over a hundred years. Only in more recent years have we had the "earth ground" (green) conductor separated from the "neutral" (white) conductor. Before today's three conductor, three prong setup, there were the two prong polarized types. Before that, they were not polarized, posing a definite shock hazard. The polarzied type was an effort to ensure that the "hot" was not on the chassis, however that did not always work. Someone finally got smart and added the third conductor for the "earth ground" which has no current except at "fault".  
I have a 1966 Gibson GA-20RVT amp that had a UL sticker. I remember it falling off and I half heartedly tried to glue it back on. I looked in the back today and still see the little circle there. It still has the two conductor cord with polarized cap. I would suspect many older amps have had those cheap little paper stickers to fall off over time. I've got a 72 Fender Twin Reverb, the sticker is there as plain as day, has a three conductor cord. I've got a Danelectro Special that does not have a sticker, can't see signs that it ever had and it has a two conductor cord. Got an Ampeg V-4 and instead of a UL sticker, it has one that says City of Los Angelos Department of Building and Safety and says approved on it. Got a Sears Silvertone Twin Twelve and it's got the UL screened on instead of a paper sticker. I checked out a couple of other pieces lying around from the sixties and they seem to have a UL sticker or stamp on them. There are other testing agencies besides UL but UL seems to be the most widely known.  
There very well may be tons of older amps that never were tested, I can't say for certain. I'd like to think they were and that the stickers just fell off with time. Maybe Fender, Gibson, Marshall would be so kind as to inform us if they did have their amps tested way back when. Or maybe UL could say.  
Sorry for being long winded here. This is the UL site: Play it safe, Terry