Amp Garage and safety issues

General discussion area for tube amps.

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Ears
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Amp Garage and safety issues

Post by Ears »

A few times over the past year or so I've occassionally been alarmed in regard to power supply questions asked and answered on the forum.

Generally it involves someone asking specific advice in the middle of a build or modification without providing schematics and/or all relevant information. IMO the very act of asking for such advice without providing such information is in itself justification for concern as most trained professionals would automatically supply this information or at least provide clear reference to a known set-up.

Whilst all HT cctry can be dangerous mucking around in power supplies offers its own set of risks.

Well intentioned advice on inadequate information can lead to injury or death. Who might then be held responsible?

No one is at fault over this situation but can not a proceedure or warning banner be put in place to alert posters to the desirability of offering a schematic of any unknown cct along with any question, especially when someone already has their hands inside an unknown circuit. Maybe all that is needed is an obvious statement to effect that including such information is far more likely elicit an accurate and speedy response.

Any other viewpoints?
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Noel Grassy
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Re: Amp Garage and safety issues

Post by Noel Grassy »

+1!
Safety is paramount IMO. This topic should be the most aggressive "sticky" in each topic's folder at Amp Garage. :!: An adequate level of electrical safety measures needs to be in place to
CYA, don't they?

Oddly, we never see posts from folks who nearly die from a mishap related to the scenario you've described. Either shame or something much worse prevents these discussions.

AC gives you a chance to let go of whatever's electrocuting you.

DC will hang on to you until you're good & dead!(Pants will be regrettable and pungent in the extreme!)

Is this any way to have your loved ones find you?
All excellent things are as difficult as they are rare__B Spinoza
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Structo
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Re: Amp Garage and safety issues

Post by Structo »

Yes, it should be a sticky on top of each section with a warning about lethal voltages.

I posted a thread a few months back that had a poll about whether or not you have been shocked while working on an amp.
Most had.

It's kind of like riding a motorcycle, there are those that have been down and those that will go down in the future.

I got zapped pretty good one time while probing an amp.
Got careless and was resting my probe hand on the edge of the chassis, I had a switch there for the OT primaries and my hand touched that!
Real eye opener!
Tom

Don't let that smoke out!
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Monkey Boy
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Re: Amp Garage and safety issues

Post by Monkey Boy »

I agree that this would be helpful. I think most of us, even us newbies, have heard of the dangers, but the more info we have available the better.
Specific warning and dangers and ways to avoid them, no matter how remedial they may sound would be good to have since many non pros use this page for reference. I know I do.
fperron_kt88
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Re: Amp Garage and safety issues

Post by fperron_kt88 »

Fully agree, these HV circuits command respect.

I don't know about the liability issues though. It would certainly be very interesting to clear the subject.

Some forums did it within the basic rules (the soldano clone one I believe), where you have to accept a set of rules to get your password (and even to see the posts). The said rules clearly underlined the fact that you could kill yourself getting zapped.

Once warned...
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jjman
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Re: Amp Garage and safety issues

Post by jjman »

When I was young TV sets had tube in them and many regular people removed, tested, and installed their own tubes. My parents would tell me not to go near the back of it since it could electrocute me even when unplugged. Of course I didn’t know what a cap was but I knew something was in there. Nowadays people don’t grow up with that warning since their parents are not removing the back of their TV every couple of years.
If it says "Vintage" on it, -it isn't.
Andy Le Blanc
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Re: Amp Garage and safety issues

Post by Andy Le Blanc »

maybe a disclaimer of liability would be best....... saftey is the resonsibility
of each individual member/reader ......
lazymaryamps
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drhulsey
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Re: Amp Garage and safety issues

Post by drhulsey »

Most of the time when I read posted questions that give superficial descriptions of the electronic situation it is followed by this post:
"Schematics? Gut shots? More information on the circuit would get you better advice."
I have followed this forum for about 2 years and have seen SAFETY repeatedly stressed, although I suppose you can't stress it too much.
Noel Grassy wrote: ... AC gives you a chance to let go of whatever's electrocuting you...
Yes, but 60 Hz AC is more likely to make your heart stop :?
Tim

In case the NSA is listening, KMA!
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Structo
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Re: Amp Garage and safety issues

Post by Structo »

drhulsey wrote:Most of the time when I read posted questions that give superficial descriptions of the electronic situation it is followed by this post:
"Schematics? Gut shots? More information on the circuit would get you better advice."
I have followed this forum for about 2 years and have seen SAFETY repeatedly stressed, although I suppose you can't stress it too much.
Noel Grassy wrote: ... AC gives you a chance to let go of whatever's electrocuting you...
Yes, but 60 Hz AC is more likely to make your heart stop :?
Hey Doc, can you expand on that last statement?
Does it have something to do with the way the hearts frequency is or something else?
Tom

Don't let that smoke out!
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Omar
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Re: Amp Garage and safety issues

Post by Omar »

Hi guys,
If you look in the Trainwreak and Dumble Discussion forums, the Welcome message includes the following disclaimer/warning:

Disclaimer/Warning: Tube amps contain high voltages that can cause serious bodily harm. Observe all electrical safety procedures when working on tube amps. The opinions/recommendations expressed on the Amp Garage are those of the posting member and do not necessarily reflect those of the Amp Garage.

I'm not sure if this is enough of a warning. I'm no lawyer. :D

Omar
Tone by misadventure
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Aurora
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Re: Amp Garage and safety issues

Post by Aurora »

While capital letter warnings are most certainly appropriate, - as a european, I'm still quite amazed about the general level of no-brainers that ends up in the US judicial system.
As an EE pro, in general terms ( maybe not in guitar amps), all mains driven eqpt represents a possible danger, - tube amps just belong in the more "evil" end of danger. There's a lot of eqpt that are quite a lot worse in terms of possible danger, but maybe not normally tinkered with by amateurs and non-educated individuals. I know quite a few fishermen thta got stung, poking around in their radars or transmitters, looking for "it's prob'ly just a blown fuse!" ( We all know fuses blow for a reason...)

How about a sticky header in all forum sections?
Andy Le Blanc
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Re: Amp Garage and safety issues

Post by Andy Le Blanc »

that disclaimer looks like it covers you as the "forum" .....
but not me as the post'ee.....
lazymaryamps
rfgordon
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Re: Amp Garage and safety issues

Post by rfgordon »

When the Army taught me electricity/electronics back in the early 80s, most of our stuff was low voltage SS stuff. However, we did have a high voltage safety segment, since some of the early lasers had some pretty mean power supplies. I never worked on radars, and they are beasts in their own world...

In the past couple of years I've met a couple of guys who thought they could tinker with their amps because they'd had some electronics in the local trade high school or community college. The "Oh, I know all about electronics" tends to change when you say "There's 450 VDC coming off that rectifier, you know..." Fortunately, both of those guys then said something like, "well, maybe you oughta fix it...."

I think lots of modern electronics education leaves high volt stuff out altogether, since so much consumer gear is low voltage. I try to make warnings very clear to people, like "Even if it's turned off and unplugged, it still might kill yo' ass!!!!"
Rich Gordon
www.myspace.com/bigboyamplifiers

"The takers get the honey, the givers get the blues." --Robin Trower
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Omar
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Re: Amp Garage and safety issues

Post by Omar »

Andy Le Blanc wrote:that disclaimer looks like it covers you as the "forum" .....
but not me as the post'ee.....
True, but I also think the line about tube amps containing high voltages that can be lethal is also a deterrent (or at least it should be to any sensible person). Maybe a member here is a lawyer and can help us the wording of the disclaimer. The problem is that you can warn people over and over about the dangers involved but some people will still ignore the warnings and carelessly poke around an amp.

Omar
Tone by misadventure
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Allynmey
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Re: Amp Garage and safety issues

Post by Allynmey »

How about this....

Disclaimer (Please Read this Carefully):
There are POTENTIALLY FATAL HIGH VOLTAGES present in the projects discussed and documented. PLEASE DO NOT ATTEMPT TO RISK YOUR LIFE BY BUILDING THEM if you are not accustomed to working with high voltages. Look for advice from someone who is qualified. There is no guarantee of any kind provided although the members are continually refining the schematics and layouts! USE AT YOUR OWN RISK: ALL REGISTERED MEMBERS, MODERATORS, WEBMASTER, CONTRIBUTORS, WEB HOSTS, EXPRESSLY DISCLAIM ALL LIABILITY FOR INJURY OR PROPERTY DAMAGE RESULTING FROM THE INFORMATION FOUND ON THE AMPGARAGE.COM WEB SITE! ALL INFORMATION IS PROVIDED 'AS-IS' AND WITHOUT WARRANTY OF ANY KIND.

This was borrowed from the 18watt.com site and is posted for review. I'll have my lawyer review it and see if it is good. A mod from 18watt is a mod here so I will ask if they mind if I copy the warning.
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