The "All American Five", & more dangers!!

[GlennSprigg]

(Please don't move this. It's mainly about 'general' topics)..
The "All American Five" refers to the mass produced valve radios, by very many manufacturers, from the 1930's. Apart from the standard 5 tubes & their functionality, their emphasis was on 'cheapness' of manufacture. There is/was NO power transformer, and relied on the American line voltage of 110/120-v to directly feed Plates (partly via resistors), and series connected tube 'heaters' of higher Filament Voltages etc., so that no mains transformer is/was needed.  OK, I get it, but half the time, one ended up with a 'Live' Chassis for the uninitiated!? 

So many times, I've seen ccts where a 'power' switch, if any, actually switches the Neutral!  The VAST majority of power plugs I've seen in America have only 2 pins, and no 'Earth' pin. Now I know that most 'modern' plugs/sockets there now are 'polarized' by way of a slightly wider pin, but still with no Earth??  I understand too that this is 'just' 110v, not 240v like in Australia, but I don't understand the attitude. I see numerous Youtube videos where people in the U.S. plug equipment into un-switched outlets on their bench. Ok, YOU might have wired it correctly. 

In Australia, we MUST have an Earth too, unless the device/machine is 'Double-Insulated', like a certain hair dryer etc. It just seems that America is more blase' about Neutrals & Earthing ?? (And yes, I understand about isolation transformers & isolated Variacs etc.) 

[joeqsmith]

This old Crosley 718 belonged to my wife's grandparents.  A couple more tubes and it uses a transformer.   

https://www.eevblog.com/forum/repair/old-console-radio-repair/msg1455644/#msg1455644

I posted once a section from the ARRL handbook on safety.  They talk about the dangers of 110, mainly because people feel working with it is low risk and get comfortable around it.

[Tom45]

Yes, everything you described is accurate. In addition, no outlets back then had grounds nor were they polarized.

The All American Five radios were designed to be extremely low cost. The enclosures and knobs were plastic so in normal use there was no chance that a user would be exposed to a possibly hot chassis.

You are getting alarmed over practices from well over a half century ago.

Automobile seat belts and child car seats didn't exist either.  I was born in 1945 and nobody thought twice about having their children free to roam around in the back seat while driving. Today parents would be in big trouble if they did that.

Somehow most of us managed to survive radios with hot chassis and cars with no seat belts or child seats.

Were people tougher back then? Are people a bunch of wimps now? I'll leave that to others to decide.

[16bitanalogue]

Were people tougher back then? Are people a bunch of wimps now? I'll leave that to others to decide.

Neither. It has more to do with safety, policy, and the squeaky wheel. "Unsafe At Any Speed" is what sparked the safety revolution in the automobile industry in the US.

Are manufacturers responsible to ensure that their products can be used safely (seat belt) even though the individual may not use that mechanism (seat belt). Let's have some real talk. People will be stupid and cause accidents, so additional safety mechanisms are, I would argue, value added.

When do they become intrusive and/or political is the question IMO. See mandatory back up camera because Mom ran over her daughter while backing up. Tragic. Truly. But a necessity?

[rstofer]

So many times, I've seen ccts where a 'power' switch, if any, actually switches the Neutral!  The VAST majority of power plugs I've seen in America have only 2 pins, and no 'Earth' pin. Now I know that most 'modern' plugs/sockets there now are 'polarized' by way of a slightly wider pin, but still with no Earth??  I understand too that this is 'just' 110v, not 240v like in Australia, but I don't understand the attitude. I see numerous Youtube videos where people in the U.S. plug equipment into un-switched outlets on their bench. Ok, YOU might have wired it correctly. 

You must have been living in some pretty old housing because U-ground receptacles have been required since 1951 for the laundry and eventually covered the entire house by 1962.  Polarized receptacles have been available since the 1880s but not mandatory until 1962 when the NEC required receptacles to be both polarized and grounding but they were in common use much earlier.

I use power outlet strips on my bench and most have switches.  I have never used the switching feature but it does exist.  There are a number of GFCI device configurations and I suppose a receptacle style could be used on a bench.

Today we have a requirement for arc-fault breakers serving certain areas of the residence and GFCI protected outlets in many others.

Lowe's still carries 2 wire unpolarized plugs.  I saw some on the shelf the other day when I was looking a 2 wire polarized plug which they didn't have.  There are a lot of two-wire applications including table lamps, toasters, hair dryers and carving knives.  Mostly, it works out fine.

[rrinker]

 Our house was built in the early 50's. There were no grounded outlets in the entire place. We had to add them when needed for newer appliances. Grounds WERE run to the boxes, but all of the outlets were basic 2 prong type.

 Paul Carlson isn't joking when he says those All-American 5's can be dangerous - and when you're literally a young player and your life flashed before your eyes, it doesn't take long. A neighbor down the street who was moving knew I had an interest in electronics, so he gave me a huge box full of stuff - components, built up devices which I had no idea, and a couple of old tube radios, one AM only (in retrospect, an AA5 design) and an AM/FM one. The AM/FM was in working condition and I actually used it for a while. The AM one had the large plastic tuning 'knob' (it was a huge wheel) snapped off. I wanted to see if it was otherwise working, so i was using an insulated handle screwdriver to reach down in and turn the tuning capacitor. All went well until my hand slipped down to the shaft of the screwdriver. Standing on the cement floor of the basement, the high voltage froze me in place. Through the windows, I could see my Mom and some others out on the patio, but I couldn't call out. Eventually I started shaking enough that the screwdriver came away from the tuning cap. It seemed like I had been frozen there for 15 minutes, but it was probably more like 15 seconds. I was damn lucky, and I developed a healthy respect for high voltage circuits after that.

 As for "Unsafe At Any Speed", don't get me started on Ralph Nader. There was nothing inherently wrong with the Corvair, that same swing arm suspension had been is use for decades in VW Beetles and Porsches, among others.

[chris_leyson]

I have a Bush DAC90A which I believe was manufactured up until about 1957. AC/DC 5 valves and has a double pole single through mains switch so safe when switched off. I really like the loop antenna mounted on the side, you can turn the radio around and null out the worst of the local QRN. I'm still considering retro fitting an isolation transformer but finding one that fits and gets rid of the hot dropper resistor is going to take a bit of work.

[james_s]

There are vast numbers of houses in the US built in the period shortly after WWII that do not have grounded receptacles, both of my grandparents lived in such homes. Many of those receptacles are polarized but most plugs of the era were not.

As someone else said, these radios were from a different era that had different attitudes about safety. They were born from the Great Depression, designed to be as cheap as possible so as to be affordable by ordinary people, the classic AA5 was the VW Beetle of radios. They were designed to not have any exposed metal parts that could be live but this safety margin could be lost if the radio was damaged. People were occasionally killed by them, especially from trying to use one while in the bath or shower if it had a missing knob or back cover which allowed exposed metal to be live.

Things were just different back then though, people didn't have the same expectation of someone else looking out for their safety that they have today. I suppose compared to glass oil lamps, gas, and exposed flames used for a majority of lighting just a few short decades earlier these radios did not seem all that dangerous.

For what it's worth, I have a couple of vintage AA5 radios and I use them, they don't worry me. I'm aware of the hazards and I make sure the back cover is intact and the knobs are in place, I don't leave them plugged in all the time and I don't have kids. Personally I quite like the design, it's very elegant, extremely simple and yet it performs remarkably well in most cases. This thread really seems like mountains out of mole hills, the world is dangerous, there are countless things all over trying to kill you if you're not careful, enter at your own risk.

[james_s]

As for "Unsafe At Any Speed", don't get me started on Ralph Nader. There was nothing inherently wrong with the Corvair, that same swing arm suspension had been is use for decades in VW Beetles and Porsches, among others.

The Corvair was a fascinating car, and extremely innovative for GM when compared to everything else that was coming out of Deteroit at the time. They were really thinking outside of the box with that one, it had some unusual handling characteristics compared to the American land yachts of the time but I'd argue that they were no less safe than countless other small and inexpensive cars of the era.

[GlennSprigg]

There are vast numbers of houses in the US built in the period shortly after WWII that do not have grounded receptacles, both of my grandparents lived in such homes. Many of those receptacles are polarized but most plugs of the era were not.

As someone else said, these radios were from a different era that had different attitudes about safety. They were born from the Great Depression, designed to be as cheap as possible so as to be affordable by ordinary people, the classic AA5 was the VW Beetle of radios. They were designed to not have any exposed metal parts that could be live but this safety margin could be lost if the radio was damaged. People were occasionally killed by them, especially from trying to use one while in the bath or shower if it had a missing knob or back cover which allowed exposed metal to be live.

Things were just different back then though, people didn't have the same expectation of someone else looking out for their safety that they have today. I suppose compared to glass oil lamps, gas, and exposed flames used for a majority of lighting just a few short decades earlier these radios did not seem all that dangerous.

For what it's worth, I have a couple of vintage AA5 radios and I use them, they don't worry me. I'm aware of the hazards and I make sure the back cover is intact and the knobs are in place, I don't leave them plugged in all the time and I don't have kids. Personally I quite like the design, it's very elegant, extremely simple and yet it performs remarkably well in most cases. This thread really seems like mountains out of mole hills, the world is dangerous, there are countless things all over trying to kill you if you're not careful, enter at your own risk.

Thank you for your (and others!) reply.  I understand that 'standards/safety' was different back then. And here in Australia too, our original vehicles had no seat-belts etc.  And we had people back in the 40's/50's unplugging a light-socket overhead, to plug in an electric Iron.

Now though, all light sockets must have an Earth wire present, whether used or not!, in case it is ever changed to say a metal bodied Fluoro fitting. And I see/review countless relatively 'modern' videos on Youtube etc, where they are still using/connecting 2-pronged plugs/cables to countless pieces of equipment. Correct me if I'm wrong, please, but it seems that 110-v is just considered 'bitey' there, as opposed to our 240-v, even today??  I know it's not, but even today they don't SEEM to adhere to the same Earthing standards we do???   

[TimFox]

When the AA5 sets were first designed before the War (typically 12SA7, 12SK7, 12SQ7, 50L6, and 35Z5), there was still domestic power distribution of 110 V DC in certain parts of the US, especially in the northeast.  Consolidated Edison in New York finally ceased DC distribution totally in 2007.  With the transformer-less “AC-DC” circuits, the radio could work with either supply. 
I have a classic E H Scott merchant-marine receiver that has a more complex AC-DC circuit, since DC was common on such vessels during WW II.  The DC within the box was (almost) isolated from the metal chassis, and hermetic “bathtub” capacitors bypassed the cathodes, screens, grid returns, etc. to the chassis.

[james_s]

Now though, all light sockets must have an Earth wire present, whether used or not!, in case it is ever changed to say a metal bodied Fluoro fitting. And I see/review countless relatively 'modern' videos on Youtube etc, where they are still using/connecting 2-pronged plugs/cables to countless pieces of equipment. Correct me if I'm wrong, please, but it seems that 110-v is just considered 'bitey' there, as opposed to our 240-v, even today??  I know it's not, but even today they don't SEEM to adhere to the same Earthing standards we do???   

Yes 2 prong (non-grounded) cords are still common here, I don't recall ever seeing a lamp with a grounded cord. 120V can and does occasionally kill people but it's pretty rare. I've been bit by it numerous times and I'm still here, but it certainly can be dangerous. I'm actually not sure why lamps aren't grounded, even those with exposed metal parts. Years ago I had one of those halogen torchier lamps in my office and a wire had chafed where it passed through a metal nipple making the entire lamp live. I thought I'd felt a tingle from it on occasion but then one day I was moving a PC and the end of the VGA cable bumped the post of the lamp and BANG. After that I disassembled the lamp and realized what had happened.

[16bitanalogue]

As for "Unsafe At Any Speed", don't get me started on Ralph Nader. There was nothing inherently wrong with the Corvair, that same swing arm suspension had been is use for decades in VW Beetles and Porsches, among others.

The Corvair was a fascinating car, and extremely innovative for GM when compared to everything else that was coming out of Deteroit at the time. They were really thinking outside of the box with that one, it had some unusual handling characteristics compared to the American land yachts of the time but I'd argue that they were no less safe than countless other small and inexpensive cars of the era.

This goes beyond the Corvair itself. Nader's book sparked the safety revolution in the automotive industry. No one could reasonably argue that what has happened since was for naught.

Per Peter Kohler (retired GM engineer from the video):

"If you know what you are doing you can drive a Corvair." That right there is a red flag that such a car should not be a daily driver. Not only should I have a license, but like Hagerty I should be a race car driver to "know what I am doing." Peter goes on to state that other cars share the same type of suspension and implies that it is not that big of a deal. Sorry, but they are different cars that will have different handling capabilities. Per his own comparison of Corvair vs Porche. This sounds like a bitter, old man yelling at a cloud. These statements are immediately followed from Jim Musser, Head of GM Engineering at the time, "The problem was too much weight transfer to the rear axle...causing oversteering and eventually go out of control."

Hell, at the end of Hagerty's video he states:

"I think of the Corvair as a sacrificial lamb that motivated Nader to write a book that got the industry to make some initially painful changes that ultimately proved necessary."

Oof. Personally, I would not die on this hill.

[bob91343]

I agree with much of the above.  I recall being irritated on the freeway by a jerk driving a Corvair.  He was tailgating me at one point and I slammed on the brakes.  He reacted quickly but due to the piece of garbage he was driving, immediately lost control.  His vehicle started to spin out and, while he didn't hit anyone, I suspect his adrenaline level took a big jump.

The hot chassis of the AA5 presented some safety issues but I have never heard of a case where someone was electrocuted by 120 Volts.  My first radio was a one-tube regenerative broadcast radio with a resistor line cord that kept me warm on many a winter night.

I have been around the block a few times and have many stories to tell, although very few are interested.  The number of times I have been zapped by 120V and more, rf burns, and other stuff is so many that I lost count long ago.  Inhaling solder fumes and paint spray, grabbing the wrong part of the soldering iron, I could go on.  I have made it to nearly 88 years and am still healthy and active and still have all my fingers and both eyes.

[themadhippy]

A bigger risk  than the lack   of earthing in lighting circuits is the existence of the ES lamp base

[amyk]

A lot of appliances today are not that much different; plenty of them use capacitive droppers to power control electronics, so no isolation, but the outer housing and user-facing parts are nonconductive. With TVs, I believe "hot chassis" continued into the 70s and later.

[Electro Detective]

A bigger risk  than the lack   of earthing in lighting circuits is the existence of the ES lamp base

No contest    and the aussie bayonet push and twist socket isn't any better, but easier than screwing around   

I'll bet a lot of dim bulb testers come poor mans current limiters out there, have the active line wired to the bulb socket and or bypass switch,
their tinkering owners just begging to be zapped real good one day,
or unattended kids messing about in the workshop sticking their finger in the socket, or curious cat, dog, or lizard sticking in the tongue

FWIW and I may not be the first with the idea..   
but my dim bulb tester/s are wired with the confirmed Neutral, to the ES and or bayonet base, not the Active.   
It works the same in use afaict and little to no chance for a zap with no lamp attached, assuming that's the only item handled or touched by accident

i.e. you would be touching an exposed earthed Neutral socket whilst you are earth/grounded yourself, be it on concrete, tiled floor or grounded bench/devices etc
so in theory and practice, assuming everything in the mix is correctly wired, nothing should happen, not even a tingle
and it's what two multimeters agreed on.. 

Add to that, for switching in the DUT in or out, that switch MUST be a double pole type, so OFF really means OFF

If you play with fire and really need a no brainer OFF OFF OFF, consider an addon three pole switch to kill all three wires, placed wherever you see fit


Now HONESTLY:    how many members here have their dim bulb testers wired with the Active 120 or 240 volt line to the socket base ? 

If I'm wrong about all this, please correct 

but 'Neutral to socket base'  works for me and no dramas yet with zaps, RCD breaker trips,
or current limiting performance as I've done A-B tests with flipped polarity to confirm identical performance,
and no earth/neutral leakage issues passed on upstream or downstream

YMMV + EMMV applies

and everyones fav Disclaimer 'DO NOT try this at home, and if stupid enough to attempt it, you do so at YOUR OWN RISK'

 

[Miti]

Were people tougher back then? Are people a bunch of wimps now? I'll leave that to others to decide.

Yes.

[Electro Detective]

Were people tougher back then? Are people a bunch of wimps now? I'll leave that to others to decide.

They're wimps because the only weights they lift are smartphones,

and brained to believe with all the information available at their fingertips, as well as watered down/dumbed down diplomas and qualifications,

that they have more intelligence, resourcefulness  and smarts than previous generations,
generations who could survive and entertain themselves with bare essentials,
no electricity, no batteries, no 'internet'.. zip nada etc   

Talk about these wimps being easy pickings for suckers and ripe for mass deception

LOL, I forgot, they are already there now and clueless to it,
they better ask their mate google to suss it all out for them and contribute some clever comeback replies here 

  
 

[themadhippy]

and the aussie bayonet push and twist socket isn't any better, but easier than screwing around

At least with newer, better quality BC holder's  you have to physically  push the pins down before you get to feel the power

[schmitt trigger]

Back in the vacuum tube days, if one repaired electronic equipment, one acquired experience by getting  burned, shocked or cut.

Those were the good old days.   

[CatalinaWOW]

It all depends on what your definition of terribly unsafe is.  Over the last few decades the decimal point has moved several places.  I now watch national news items wringing their hands about something that has  "doubled the death rate".  From 2.4 per million to 4.2 per million.  Personally, I have trouble worrying about anything that is measured in per million, but that doesn't seem to be the general attitude these days.  Arguments about whether this is a good thing or a bad thing are best done in a pleasant setting with an adequate supply of beer.

[james_s]

This goes beyond the Corvair itself. Nader's book sparked the safety revolution in the automotive industry. No one could reasonably argue that what has happened since was for naught.

Per Peter Kohler (retired GM engineer from the video):

"If you know what you are doing you can drive a Corvair." That right there is a red flag that such a car should not be a daily driver. Not only should I have a license, but like Hagerty I should be a race car driver to "know what I am doing." Peter goes on to state that other cars share the same type of suspension and implies that it is not that big of a deal. Sorry, but they are different cars that will have different handling capabilities. Per his own comparison of Corvair vs Porche. This sounds like a bitter, old man yelling at a cloud. These statements are immediately followed from Jim Musser, Head of GM Engineering at the time, "The problem was too much weight transfer to the rear axle...causing oversteering and eventually go out of control."

Bullshit.

All cars have handling characteristics that vary from other types of cars, a significant part of driving is knowing what you're doing. A high performance RWD sports car has a tendency to oversteer, FWD cars have torque steer, big older American cars understeer, trucks and SUVs have a high center of gravity making them prone to rollovers, a pickup truck with no load is very light in the back end which adds its own unique handling quirks, I could go on and on. As a driver it is 100% YOUR responsibility to learn the handling capabilities of the car you are driving and stay within the limit. You don't have to be a race car driver to safely drive a Corvair, you just have to be modestly competent and have a basic understanding of physics, something you should have to drive ANY car. The similarly configured VW Beetle he mentioned was safely driven by millions of people for decades. It was nowhere near as safe as modern cars but people somehow managed. The AA5 radios that started this thread, the VW Beetle, the Corvair, the Pinto, these were all designs that were made to satisfy a goal of low cost, (and high fuel efficiency in the case of the cars) making them affordable to as many people as possible. Designs that required compromises to attain these goals within the technology available at the time. Maybe kids these days are just completely out of touch with how things were just a few decades ago before the influx of incredibly cheap technology and toys that we have today.

Yes Nader's book did help kickstart some important changes, but calling the Corvair "unsafe at any speed" is pure hyperbole. Sensationalism to sell books.

[Tom45]

... Consolidated Edison in New York finally ceased DC distribution totally in 2007. ...

To be fair to Con Ed, I think they carried on with DC service for such a long time because there were a few elevators in NYC that used DC motors.  Substituting AC motors and controls was apparently deemed to be a bigger problem than just continuing DC service to the few ancient DC installations.

A search brought this article:
https://cityroom.blogs.nytimes.com/2007/11/14/off-goes-the-power-current-started-by-thomas-edison/

Apparently the hold outs haven't converted to AC. They just installed AC to DC converters on site.

[james_s]

To be fair to Con Ed, I think they carried on with DC service for such a long time because there were a few elevators in NYC that used DC motors.  Substituting AC motors and controls was apparently deemed to be a bigger problem than just continuing DC service to the few ancient DC installations.

A search brought this article:
https://cityroom.blogs.nytimes.com/2007/11/14/off-goes-the-power-current-started-by-thomas-edison/

Apparently the hold outs haven't converted to AC. They just installed AC to DC converters on site.

Makes sense. I could see it costing many millions to retrofit the elevators in an old building with a modern system. Assuming the old equipment is still serviceable then installing a rectifier to supply DC sounds like a pretty reasonable option. It's not like you can just swap out the motor, a conversion in a historic building would be opening a big can of worms.