Vacuum tubes

[Alpo]

I don't know anything about 'em really. They were before my time.

 

But if you had a shortwave radio, and a tube blew, and there were television sets available, what would be the possibility that a tube out of one of the TV sets would work in the radio?

[Four-Eyed Buck,SASS #14795]

Depends on the type of tube. I can barely remember the tube type TV's

[Duffield, SASS #23454]

It depends very much on the type of tube.  Also the age of the TV set, older ones tended to have more tubes available.

I got in on the tail end of the vacuum tube era, and they are not missed. 

 

Duffield

[Matthew Duncan]

21 minutes ago, Alpo said:

I don't know anything about 'em really. They were before my time.

 

But if you had a shortwave radio, and a tube blew, and there were television sets available, what would be the possibility that a tube out of one of the TV sets would work in the radio?

Does one engine oil filter fit ALL vehicles?  No.  You might find a few that are interchangeable.  The same is true with vacuum tubes.

[Subdeacon Joe]

As long as the tube designations are the same,  yes.  If you think about it (even if you don't think about it) television is radio with an output via cathode ray tube.

[Trailrider #896]

There were a bunch of different vacuum tubes: diodes, triodes and I don't remember what all. It would be kinda like stuffing .45LC into a .44 Mangle-em or visa versa.  It would depend on the type of tube and the rating.  Interesting thing about vacuum tubes in electronics...when the Russian pilot defected with the MiG-25, our troops found virtually all it electronics used tubes.  After laughing their posteriors off, our guys suddenly realized that if the plane and pilot had to fly through an ionizing EMP (which would have eventually killed the pilot), the radiation, which would have fried integrated circuitry of the time, would have only temporarily knocked out the vacuum tubes! 

Stay well and safe, Pards!

[Barry Sloe]

It depends on where you are as to when or if the vacuum tube era ended.  In '92 I toured a relatively new Russian cruiser. It was set up with vacuum tubes all over the place. 

 

BS

[Forty Rod SASS 3935]

I got a great life lesson as a result of a blown tube on our 1951 RCA console TV, radio, record player sets.

 

A friend of Dad's....John D. Rindlesbacher...who ran the local TV store came over to fix it.  We muscled the big machine out from the wall and John D. put his machinery and skills to work.  After a bit he pulled a tube out a replaced it and showed us that the Tv worked just fine now.  Dad asked how much and John D. told him the bill was $22. 44.

 

Dad about had a fit.  "Come on John D.  $22.44 for that little tube?"

 

John D. was putting his gear away and then told Dad, "No, Tom, forty four cents is the sales tax, two dollars is for the tube, and twenty dollars is for knowing which tube."

 

Dad grinned and turned to me and said "Remember this.  Never be afraid to tell someone 'I know more than you do.  Pay me'."

 

I made a lot of my clients a lot of money doing just that.  In the meantime, I made good money making them rich.

[Alpo]

Alas Babylon. PAW novel taking place in Florida in the mid-50s. They got their electricity from Orlando, and Orlando got nuked so they had no power. They were getting all their information from the one guy's shortwave radio set, that he was running off car batteries.

 

Then, "Early in May a tube in the Admiral’s radio flared and died, cutting off the voice of the world outside."

 

And I thought about all those dead television sets in town - useless because there was no electricity - and wondered whether a tube from them would work.

 

It's true that one oil filter will not work on all cars. But there are only so many types of oil filters made. If I needed an oil filter, and I had access to the parts house of the Chevy lot, and the Ford lot, and the Buick lot, and the Dodge lot, etc etc, I could probably find a filter that would fit my Yugo.

 

I don't know if all of the tubes in a certain television would be the same type, or if they would have multiple types of tubes. But if this house had an RCA, and this house over here had a Philco, and this house had a General Electric, it seems like I would have a chance of having all sorts of different tubes.

[Go West]

My older brother used to get old radios and tvs that didn't work (some from the dump) and would take tubes out to test at the pharmacy. Some of those cabinets had really fancy veneers and/or Art Deco styling. Anyway, a couple of bucks and a bit of time and he got a lot of them going. Some cabinets that had useless guts were put to other purposes. 

[Marshal Mo Hare, SASS #45984]

Ahhh, I need to write about duga 1, 2, 3, the Russian woodpeckers, over the horizon radars, one of which was moved by truck out of the Chernobyl Exclusion Zone in the days following Apr 26, 1986.  The aluminum antenna structures were left in place.  All discrete electronics and tubes in a semi underground facility hundreds of meters long.

[Capt. James H. Callahan]

I remember tube testers at stores when I was a kid. Had dozens of different pattern plugs. IF the tube fits and IF the tubes is good it might work, I dunno. Not my field of expertise.

JHC

[Crazy Gun Barney, SASS #2428]

I miss the tube tv's.  When I was a kid, I remember going down to Thrifty's with tubes from my grandma's TV to test them and get new ones.  I could always convince her that we (her and I) "needed" ice cream cones for the walk back home.  She wasn't hard to convince... 

[Subdeacon Joe]

52 minutes ago, Alpo said:

don't know if all of the tubes in a certain television would be the same type, or if they would have multiple types of tubes. But if this house had an RCA, and this house over here had a Philco, and this house had a General Electric, it seems like I would have a chance of having all sorts of different tubes.

 

There will be a half dozen or more different tubes (valves to Commonwealth folks) in any tube-style set.  But  (just pulling random designation sounding numbers out of the air) a BG74JL made by GE will replace a BG74JL made by Rayovac , Philco,  et alia.  Got standardized in the early '50s.  Actually,  it was standardized before that,  but formally standardized in the early 1950s.

 

That's why the tube test machines mentioned above were universal.   

 

ADDED: 

 

Example of tube tester

[Eyesa Horg]

58 minutes ago, Forty Rod SASS 3935 said:

I got a great life lesson as a result of a blown tube on our 1951 RCA console TV, radio, record player sets.

 

A friend of Dad's....John D. Rindlesbacher...who ran the local TV store came over to fix it.  We muscled the big machine out from the wall and John D. put his machinery and skills to work.  After a bit he pulled a tube out a replaced it and showed us that the Tv worked just fine now.  Dad asked how much and John D. told him the bill was $22. 44.

 

Dad about had a fit.  "Come on John D.  $22.44 for that little tube?"

 

John D. was putting his gear away and then told Dad, "No, Tom, forty four cents is the sales tax, two dollars is for the tube, and twenty dollars is for knowing which tube."

 

Dad grinned and turned to me and said "Remember this.  Never be afraid to tell someone 'I know more than you do.  Pay me'."

 

I made a lot of my clients a lot of money doing just that.  In the meantime, I made good money making them rich.

Imagine the griping when transistors came out. Major labor was $49.95, the transistor might be $15 and only a 1/4" in diameter. "You charged me $65 to replace that little thing"! The trouble with flat rate labor in the day, was it might take 15 minutes to fix the set or it might take a couple days! Just my experience from back in the early 70's. When I first started fixing TV's and stereos, some were tube type, some hybrid, some all solid state.

[Will Kane]

Collecting and refurbishing old vacuum tube transmitters and receivers (nowadays called “boat anchors “) is a sub hobby within amateur (ham) radio.  Kinda like shooting frontiersman in CAS. There are outfits that have stockpiled new old stock vacuum tubes to cater to that market of consumers. Someone with a blown tube would probably first check the tube to see if its numbering (e.g. 12AX7) still appears on it and then go online and look for a potential supplier. 

[Chickasaw Bill SASS #70001]

I still use tube amps , and I have a small tube tester , in the shop , along with a few spare tubes 

 

  if replacing a 12ax7 , use a 7025 , about 15+% more gain 

 

might have to re bias the unit , most times it is plug and play 

 

  CB 

[The Original Lumpy Gritz]

2 hours ago, Subdeacon Joe said:

As long as the tube designations are the same,  yes.  If you think about it (even if you don't think about it) television is radio with an output via cathode ray tube.

Very different internally as to voltage between radio an TV.

If the tube doesn't 'see' certain voltage. It won't function. 

OLG 

[Subdeacon Joe]

21 minutes ago, The Original Lumpy Gritz said:

Very different internally as to voltage between radio an TV.

If the tube doesn't 'see' certain voltage. It won't function. 

OLG 

 

 

Wouldn't the tube type (designation) be different for different voltages?

[Eyesa Horg]

If I remember right the first number is the filament voltage. 12AX7 would be a 12 volt and 6L6 would be 6. It's been many a decade!

[Will Kane]

Yes. Different tubes call for the application of different voltages on the various components of a given tube. That’s why knowing the tube numbering is important. That way. you can pull the “rotten orange” and replace it with a “good orange” rather than a “good tangerine“. In the old days, simply swapping tubes was one of the first steps of troubleshooting. Having a tube tester made it easier, but they’re not made anymore. It amazing how much a good quality used tube tester fetches on the auction sites. 

[Ace_of_Hearts]

Tubes came in many sizes and purposes as well as operating voltages for the filaments.

 

Diode tube had 2 elements (Besides the filaments) and were usually used to convert AC signals/current to DC.

Triodes were used as basic amplifiers or electronic switches.

From there it went to Tetrodes (4  elements)

Pentodes (5 elements)

And from there a myriad of other arrangement of control grids inside the tube to do different functions and do them at different frequencies..

On top of that there were different base designs  and configurations.

 

The radio in you 1950s car contained anywhere from 4 to 9 tubes as well as a vibrator which changes the 12V DC current to AC to power the filaments in the tubes. The radio in you 1950s home contained the same number of tubes but usually the filaments were in series as they ran on 115v house power. The tubes did exactly the same job but the 12V filaments in the car radio were not interchangeable with the home radio.  

There are literally thousands of different types of tubes that were designed for specific purposes.

 

We still use vacuum tubes today. Most high end sound amplifying systems are vacuum tube do to the ability to amplify the primary sound wave and also the harmonics  that reenforce the original wave and create tone to the sound.

 

The magnetron in your microwave oven is a tube. The x-ray in you dentist office is a tube.

 

All tubes were given a number. There are very few that are interchangeable. Your typical tube tester in the store or even the one your TV repair man had only covered a small portion of the different tubes that were available.

 

 

[Happy Jack, SASS #20451]

It is interesting that vacuum tube audiophile components are making a comeback. They have a "Warmer" sound than solid state. The main reason they went out of style was keeping the bias working right as the tubes aged. The new units have built in meters to make the job easier.

[Sedalia Dave]

28 minutes ago, Subdeacon Joe said:

 

 

Wouldn't the tube type (designation) be different for different voltages?

 

Yes a 12AX7 is the same no matter what it is in.

 

Some of the high voltage sweep tubes used in TVs could be repurposed as RF amplifiers for Ham radio and were quite valuable. For a few years the only sources of tubes was salvage or NOS (New Old Stock) Then importers discovered that it was profitable to import Svetlana tubes from Russia. 

These were essentially RCA tubs built under license in Russia and were very good quality. The Former Soviet union currently builds some very good vacuum tubes and the odds of any given tube in modern equipment being of Russian origin are very high.

 

Thanks to the high end audio market vacuum tubes are still being manufactured including some in the US.

The reason vacuum tubes are here to stay is sound quality. When you push solid state devices to their limit they go from sounding ok to sounding really really bad pretty quickly. When you do the same with Vacuum tubes they go from sounding really good to sounding not so good very gracefully. Another plus is vacuum tubes will tolerate some abuse without failing. Solid state devices fail rapidly when abused.

 

I have seen vacuum tubes abused to the point where the glass got so hot that it deformed and failed. Others were so hot the plate melted.

 

 

[Alpo]

I should have read another page before I posted the question. They tried to find a replacement tube but they were unsuccessful. The admiral said that did not surprise him, as prior to the war whenever he needed any spare parts for his radio he had had to order them from the factory in New England.

 

I'm glad I posted the question though. This has been a very interesting thread. I learned a lot.

[Happy Jack, SASS #20451]

I have a big box full of tubes in storage. Unfortunately none are high power output tubes I could use for audio amplification.

 

Along the line of audiophile tube amps:

If you have the money amps from Audio research would be wonderful.  However for most of us we would have to settle for Rogue Audio.

[Hardpan Curmudgeon SASS #8967]

Excellent read, Alpo.   

[Texas Lizard]

Also depends on the age of the shortwave receiver...Mine was a RME 69...Used a 80 for power supply area...And the others were 6D7 and 6C7 if I remember right....Not to easy to find...Rewired it for more modern tubes in the mid 60s...High school electronics project...

 

Texas Lizard

[Sgt. C.J. Sabre, SASS #46770]

6 hours ago, Subdeacon Joe said:

 

There will be a half dozen or more different tubes (valves to Commonwealth folks) in any tube-style set.  But  (just pulling random designation sounding numbers out of the air) a BG74JL made by GE will replace a BG74JL made by Rayovac , Philco,  et alia.  Got standardized in the early '50s.  Actually,  it was standardized before that,  but formally standardized in the early 1950s.

 

That's why the tube test machines mentioned above were universal.   

 

ADDED: 

 

Example of tube tester

I remember these. The T.V. would stop working. We'd remove the screws that held the fiberboard back to the wooden cabinet, get told by Dad, "Don't touch the condenser, it'll electrocute you." Remove the tubes, wrap them in newspaper, load them into the basket on my bicycle, and ride to the Drug Store. 

Once there, place each tube into the proper socket, (as you can see, there were a LOT), and test them in turn. When the bad one was found, open the bottom of the test cabinet and find the replacement. 

Ride back home and put the T.V. back together.  "Don't touch the condenser, it'll electrocute you." Screw the back on and plug it in.

[Three Foot Johnson]

My AE "A" school in the Navy in '74 still thoroughly covered vacuum tube theory. I had a piece of test equipment in my shop called a MATS (Mobile Automated Test Station) stand, which was a wheeled cart with a tow bar, and about the size of a Smart Car, meant to be used on the flight line, really. It ran on vacuum tubes, and when I powered that thing up, it notably raised the temperature in there after awhile. 

[The Original Lumpy Gritz]

5 hours ago, Subdeacon Joe said:

 

 

Wouldn't the tube type (designation) be different for different voltages?

Yes-there were some exceptions. 

OLG

[Buffalo Bill Mathewson, 37826]

1 hour ago, Sgt. C.J. Sabre, SASS #46770 said:

I remember these. The T.V. would stop working. We'd remove the screws that held the fiberboard back to the wooden cabinet, get told by Dad, "Don't touch the condenser, it'll electrocute you." Remove the tubes, wrap them in newspaper, load them into the basket on my bicycle, and ride to the Drug Store. 

Once there, place each tube into the proper socket, (as you can see, there were a LOT), and test them in turn. When the bad one was found, open the bottom of the test cabinet and find the replacement. 

Ride back home and put the T.V. back together.  "Don't touch the condenser, it'll electrocute you." Screw the back on and plug it in.

When dad was out of town I became the TV repair guy. Mom had to take me to the drug store so I could test the tubes. I was lucky as I never knew about the condenser thing with the stored high voltage until several years later in a high school electronics shop class.

[Trailrider #896]

Nowadays try and find a "T V repair shop"!  Costs more to mess with than the thing is worth.  Just throw it out and buy a new one...cheaper.   

Stay well and safe, Pards! (Wife got her 2nd shot this morning; me on Thursday.)

[Marshal Mo Hare, SASS #45984]

The earliest computers used tubes and relays.

 

https://en.wikipedia.org/wiki/Vacuum_tube_computer

[Alpo]

I thought the earliest (and still the best) computers use synapses and neurons.