Ouch!

[SurreyNick]

Ouch!

Just read this on an eBay auction for a complete valve radio chassis.

"THIS AUCTION IS JUST FOR THE INTERNALS THERE IS NO WOODEN CASE. I WIRED THIS RADIO UP ABOUT THREE MONTHS AGO. ALL VALVES LIT UP, COULD NOT PICK UP ANY RADIO STATIONS. I WIRED A CD PLAYER INTO THE PHONO SOCKET AND LOW AND BEHOLD THE AMP WAS WORKING. NOTE WHILE I WAS DOING THIS I GOT A SMALL SHOCK OFF OF THE CASING. I AM NO RADIO ENGINEER SO I AM SELLING THIS AS SPARES OR REPAIR ONLY"

Uhhh! Just the thought of it makes me wince. Live chassis perhaps!

Nick

[Terry]

Unlikely, as it has a gram input (although not entirely unknown!)

As it was a slight shock, I'd guess AC chassis with two core mains lead. It would be quite common to find a voltage on the chassis due to effects such as the inter-winding capacity of the mains transformer, for example.

Once upon a time, of course, such a set would always be used with a good aerial and earth connection, so no shocks!

[Joe]

Unlikely, as it has a gram input (although not entirely unknown!)

Indeed.   http://golbornevintageradio.co.uk/forum/...hp?tid=737&page=3&highlight=ekco
— Joe

[SurreyNick]

OK. That's something of a relief, but it was partly the blasé way in which the seller just assumed it was safe to plug in and touch the chassis. At his own admission he has (it seems) no knowledge of what he was doing. I hate to think what the consequences might have been if it was live.
Nick.

[Yorkie]

Maybe he's trying to win the Darwin Award Nick? (For the 'non-survival of the stupidest' that is!)

They walk among us. 

[SurreyNick]

LOL. Very good David
N.

[Terry]

The trouble is, Nick, that without details of the chassis it is impossible to say what happened. If it is a live chassis model with a capacitor isolated phono input it is no less dangerous than a AC/DC TV with a capacitor isolated aerial socket.

If you are completely isolated you can play around with a live chassis set with relative impunity - provided that you know what safety precautions to observe.

In this case we don't know that he wasn't standing on a damp shed or garage floor with slightly damp footwear and a live chassis ...

[Nick]

Maybe he's trying to win the Darwin Award Nick? (For the 'non-survival of the stupidest' that is!)

Technically, the Darwin Awards are only for people who manage to kill themselves by completely stupid means, BEFORE THEY HAVE CHILDREN.

The point being, of course, that they are removed from the gene pool by Darwinian Selection...

[Terry]

The best part of 50 years ago I had to demonstrate to a Factories Inspector that my workshop was an earth-free area with the earth leads of soldering irons, test equipment, etc. all lifted.

He went away satisfied but I wondered if he ever investigated the working environment of a field engineer who constantly walked through front doors in the course of a day, each one revealing its own unknown hazard zone ...

As one colleague discovered the hard way the wallpaper on an outside wall of an old house, after being subjected to a torrential downpour which had leached through the porous salt laden brickwork, could be surprisingly earthy right behind the TV he was working on ...

After I left the retail trade I worked on a cable network in the City. I wonder what a Factories Inspector would have made of a special receiver comprising a modified ITT-KB VC100 chassis with a three-core mains-lead, an earthed special multi-band VHF tuner and mains isolation on the IF connection between tuner and chassis.

Add to this that the top of a metal filing cabinet was a common place for one of these to be sited and you really had to have your wits about you ...!