Stereophile's Jim Austin disagrees w Atkinson; says tubes have something that can't be measured

[Trell]

I’ve had lucid moments between electrocution incidents, too (I believe).

I learned fairly quickly at a young age not to touch anything inside those old tube radios, especially with power on.

 

[mhardy6647]

My father was a broadcast engineer in the late 1950s (with a First Class FCC Radiotelephone Operator's license, which he was quite proud of and which he maintained for a long time), but by the early 1960s he was a self-employed TV repair person. He used to get shocked fairly regularly*, but the most common outcome of such an event was a gash on his arm as he reflexively jerked it out of the innards of whatever TV he was troubleshooting.

______________
* One of his standard techniques was using an axial lead capacitor with fairly long leads to shunt a (suspected) bad capacitor. These were HV capacitors with... umm... high voltages on 'em. He was, in many cases, reaching into a TV with the back off but the chassis still installed in the set; kind of a dark, constrained environment (especially with a 'table model' TV). Once in a while, inadvertent repairperson/HV contact was made.

 

[theREALdotnet]

He used to get shocked fairly regularly*, but the most common outcome of such an event was a gash on his arm as he reflexively jerked it out of the innards of whatever TV he was troubleshooting.

I think this the most common injury with electrocution in the trade. The actual shock is usually far less of a deal than often thought.

Although, I remember assisting with the troubleshooting and repair of a depth sonar amplifier from a commercial vessel, ca. 1982. The device had a huge output tube (think 2l Coke bottle) and an anode voltage of 4kV. Everybody was slightly more apprehensive than usual about sticking their probes into that device…

 

[Doodski]

My father was a broadcast engineer in the late 1950s (with a First Class FCC Radiotelephone Operator's license, which he was quite proud of and which he maintained for a long time), but by the early 1960s he was a self-employed TV repair person. He used to get shocked fairly regularly*, but the most common outcome of such an event was a gash on his arm as he reflexively jerked it out of the innards of whatever TV he was troubleshooting.

______________
* One of his standard techniques was using an axial lead capacitor with fairly long leads to shunt a (suspected) bad capacitor. These were HV capacitors with... umm... high voltages on 'em. He was, in many cases, reaching into a TV with the back off but the chassis still installed in the set; kind of a dark, constrained environment (especially with a 'table model' TV). Once in a while, inadvertent repairperson/HV contact was made.

I know of a electrocution where the victim had multiple broken bones as well as the burn marks. Nasty stuff. I almost broke my nose taking 40K micro Farad from a power supply. That one smartened me up big time.

 

[mhardy6647]

Not to be pedantic (me?!? perish the thought!) but I think it only counts as electrocution when it only happens once*
Otherwise, it's just getting shocked.
________________
* If you catch my drift.

 

[Doodski]

Not to be pedantic (me?!? perish the thought!) but I think it only counts as electrocution when it only happens once*
Otherwise, it's just getting shocked.
________________
* If you catch my drift.

Oh this guy was pretty near dead and was being resuscitated with CPR/mouth to mouth back in the day that when that was the method. It was my father a fireman paramedic that was administering industrial first aid to him and he convulsed, vomited in my father's mouth and then died. Horrible stuff. Industrial voltages coming from a hydroelectric dam that powered the facilities at a huge smelter and zinc fertilizer operation. I will never forget that.

 

[Timcognito]

My stick welder knocked me out at age 17 then being awaken by my crying father (actually it was his stick welder that he warned me about). Thank heavens for circuit breakers. No lie, that was fundamental in me choosing MECHANICAL Engineering as a major when I couldn't get into Architecture program at UC Berkeley.

 

[pablolie]

Oh this guy was pretty near dead and was being resuscitated with CPR/mouth to mouth back in the day that when that was the method. It was my father a fireman paramedic that was administering industrial first aid to him and he convulsed, vomited in my father's mouth and then died. Horrible stuff. Industrial voltages coming from a hydroelectric dam that powered the facilities at a huge smelter and zinc fertilizer operation. I will never forget that.

The danger of electrocution has zero to do with the merits of tubes vs solid state semi in audio designs, though.

Anyone that doesn't respect their interaction with significant levels of electricity is playing with dangerous fire. And capacitance can kill very easily. I did my MSEE here: https://www.epe.ed.tum.de/en/hsa/equipment/professorship-hsa/

Mistakes were known to be very easily deadly, and the safety rules were top level. I just wrote software honestly. But very impressive stuff and still one of the top facilities for high voltage research on the planet. Only accident I ever heard about was because somehow a rat/rodent was in the facility and during a test it got turned inside out as it exploded. Facility was closed for a month to clean out any possible unpredictability.

PS: As always, I emphasize my degree was NOT in audio. I do not work in the audio field.

 

[Doodski]

Anyone that doesn't respect their interaction with significant levels of electricity is playing with dangerous fire. I did my MSEE here: https://www.epe.ed.tum.de/en/hsa/equipment/professorship-hsa/

I never knew you have a masters of science in EE. Impressive! Electricity is like mother nature when out in the wild. It's very unforgiving but so useful if tamed and respected.

 

[Ricardus]

You start to sound like you have an agenda. :-D

I'm not sensing an agenda at all. He's just stating facts. And I agree with him.

I suspect the guy accusing others of having an agenda doth protest too loudly with their own agenda.

 

[pablolie]

I never knew you have a masters of science in EE. Impressive! Electricity is like mother nature when out in the wild. It's very unforgiving but so useful if tamed and respected.

I repeat: audio tech was nowhere on my curriculum or agenda. I claim no higher authority than anyone else in this forum when it comes to that. Just one more contributor.

My trajectory was always geared more towards the interaction of software and hardware, and I have a few patents in internet technology - not audio. I am just one more hobbyist here, albeit a tad opinionated like everyone else. :-D

 

[Timcognito]

I am just one more hobbyist here, albeit a tad opinionated like everyone else. :-D

+1 and not ashamed

 

[fpitas]

Well -- microwave ovens.

I have to assume that the really big "border blaster" transmitters (if there are any still extant) are still using water cooled tubes as the finals. But, heck, maybe there are 100 kW power transistors now??? Maybe even ICs, for all I know!

View attachment 286142

320A Vacuum Tube

The 320A Vacuum tube is a 3 element water cooled tube designed for use
as an oscillator, modulator, or amplifier at the higher power levels
and high frequencies.

Filament ratings: 35 volts at 435 amperes

Average thermionic emission: 90 amperes

Characteristics at 18 kV plate voltage and 8 amperes plate current:


Amplification factor: 30
Plate resistance: 965 ohms
Transconductance: 31,100 micromhos

Maximum plate ratings:

maximum plate voltages: 12.5 kV modulated
18 kV non modulated
20 kV rms AC
current: 15 amps DC
dissipation: 150 kilowatts

Maximum grid dissipation: 2 kilowatts
source: http://j-hawkins.com/mexblast.shtml

Oh, yeah!

You want to make a SET amp out of that. Don't you?

 

[Doodski]

I repeat: audio tech was nowhere on my curriculum or agenda. I claim no higher authority than anyone else in this forum when it comes to that. Just one more contributor.

My trajectory was always geared more towards the interaction of software and hardware, and I have a few patents in internet technology - not audio.

Electronics study for me was very challenging and so fascinating that I really went hard on hitting the books and overcame some issues I had with prerequisites for the study. It still is and I wish I had the knowledge that you peeps with degrees have. I'm thankful I have the experience I have under my belt but to be EE would be so awesome. I attempted software machine code stuff but after perusing the commands and stuff and trying it it just wasn't my thing at the time. I was told to keep at it and it gets more interesting but I was preoccupied with the component level study rather than the software. I like circuitry!

EDIT: I really enjoyed Eunix though. Is that the correct spelling?

 

[pablolie]

...

I suspect the guy accusing others of having an agenda doth protest too loudly with their own agenda.

You are entitled to your opinion, but if I have an agenda it is one I am unaware of. I am not that hard to trace online, and it is easy to see I do not work in the audio field - hence my only agenda is to try to contribute to topics with stuff I know, and sometimes stuff I believe. The latter is what always catches us out.

But I think my beliefs and intuition are as good as anyone else's... :-D

 

[fpitas]

Electronics study for me was very challenging and so fascinating that I really went hard on hitting the books and overcame some issues I had with prerequisites for the study. It still is and I wish I had the knowledge that you peeps with degrees have. I'm thankful I have the experience I have under my belt but to be EE would be so awesome. I attempted software machine code stuff but after perusing the commands and stuff and trying it it just wasn't my thing at the time. I was told to keep at it and it gets more interesting but I was preoccupied with the component level study rather than the software. I like circuitry!

EDIT: I really enjoyed Eunix though. Is that the correct spelling?

Hmmm. Maybe in time the awesome feeling will occur

 

[pablolie]

Electronics study for me was very challenging and so fascinating that I really went hard on hitting the books and overcame some issues I had with prerequisites for the study. It still is and I wish I had the knowledge that you peeps with degrees have....

Anyone that knows me also knows the first thing I say is that my nearly 30 year old degree never proved any other thing than the fact I can learn. Ask me to do a Laplace function today and be ready to be disappointed - I have never had to use it in my entire professional life.

My firm belief in what some would call a successful engineering career is to ... stay humble, and know what you think you knew is always up for revision tomorrow. You have to keep learning and overthrowing what you thought you knew. It's easy in high tech: you are *always* wrong 3 years after the fact.

I wake up every morning to have fun learning... and that includes from everyone in this forum...

 

[BDWoody]

EDIT: I really enjoyed Eunix though. Is that the correct spelling?

I'm hoping the correct spelling isn't eunuchs...

 

[Doodski]

I'm hoping the correct spelling isn't eunuchs...

Haha. I've thought about that too...LoL.

 

[diddley]

Unix