Big Power! 14000 Watt 892-R Transmitter Tube - Will It Work? Power It Up!

[@MrCarlsonsLab]

To learn electronics in a very different and effective way, and gain access to Mr Carlson's personal designs and inventions, visit the Mr Carlson's Lab Patreon page here: www.patreon.com/MrCarlsonsLab

[@cjay2]

Big-eyed thumbnnails are really not your style. I'll unsub if it continues. Just saying.

[@ambersmith6517]

WHAT A SHOW!!!! I have a toroid transformer setting on my kitchen table I hand wound about the size of your variac Mine may be a little bigger its hooked up to a home made pure sine inverter Low freq DOSE NOT mean it has to have high idle current The last inverter I built had 60 or 70 pound toroid transformer and the idle FULLY POWERED up ALL power from battery bank was around 20 watts If you don't know the secret of low idle and silent zero hum with ear on tranny it would surprise me But I don't mind sharing this info My name is Ben this is my wife's youtube A EE friend of mine after a year of using a tranny wound like I speak of told me he cant find any loses Even though it definitely has them he says it powers his whole zero grid home He has redesigned almost EVERY thing at his place to run off batteries Yes even the pcb and screen of his microwave LOL He also designed and wrote the programing for some of my inverters I tell you truth 4 or 5 years ago he had a new update for me to try He made my inverter have a built in oscilloscope He did it form a wifi update He lives few hours from me I am like forrest gump self taught nothing like you or him I very old EE from the land down under would NOT give me the answers about winding transformers I wanted I think he knew exactly what is was doing but never has said so I like forest gump fingered out how to get such low idle when winding trannys Sorry so long wish you was my neighbor I am SURE you know and have many cool stuff you have built to tinker with lol

[@dicko-200]

Patreon is taking my $ but I cannot see your videos

[@MrMoon1ight]

интересно а где использовались такие лампы ? :)

[@mannyfragoza9652]

I thought the Tube would light up as bright as the sun I guess you would need to boost the power some?

[@davelister796]

Who needs The Voice of America, we can now have The Voice of Mr Carlson.

[@agems56]

Well said, and he speaks so eloquently in layman's terms, he doesn't need to speak in "Special English!" Lol!

[@timjr02]

He's Canadian.

[@gilbertojunqueira314]

It looks like a scene from the movie Back To The Future. 😁

[@orbitingeyes2540]

We'll see him on 15m SSB with this PA tube soon 😂. He'll be able to compete with the Cubans and their old Soviet transmitters.

[@douro20]

@@orbitingeyes2540 Unfortunately that is highly illegal. The most legal thing he could do with it is using it in an RF heating system.

[@FlyingShotsman]

I once maintained a military radar system that used a traveling wave tube the size of my leg to drive a Klystron tube final amplifier that was bigger than me. The Klystron was in an enclosure the size of a small car that provided magnetic shielding and allowed liquid cooling. Voltage levels in the enclosure were so high that the conductivity of the ethylene glycol based coolant had to be monitored to prevent shorts through the cooling circuit. When the transmitter was tested into a dummy load (itself an impressive device), it sounded like a metal garbage can full of angry steel hornets. Fun times!

[@jjiacobucci]

Angry steel hornets.....quite the image evoking metaphor. Kudos !

[@imfloridano5448]

Sounds like the P.A.R. system which has that setup. The Patriot system uses a TWT as well

[@kenwatanabe2599]

AN/SPN 3x ?

[@MrAvant123]

@@imfloridano5448 Understandable if you want a fair amount of power that can frequency hop...

[@lilben869]

Doesn't sound exactly the same, but very similar to SPY radar equipment. Former SPY tech myself and I couldn't pass this video up cause it has some similarities to the electron tubes we used.

[@SundayBeastz]

*This channel is a National Treasure and this video should go viral.*

[@robertchristiano7671]

This channel never disappoints. "Thats not a Variac.... THIS IS A VARIAC"...

[@russellhltn1396]

I wonder if it used to be a dimmer for a theater.

[@rilosvideos877]

There are even much bigger VARIACs 🙂 They run on all three phases here in Europe an are capable of 10+ kVA. They are very useful as universal AC variable power supplies.

[@donl1846]

....and then some !!

[@ivarlarsen6045]

Lol :)

[@denisdespins1127]

@robertchristiano7671 oh yeah, I THOUGHT I had a big variac...nah. (Mine is max 40 Amp @220vac Input) and thanks again Paul ! You said what I was thinking Robert !

[@ctbcubed]

Back in the early 70s I worked at a 50kw AM radio station that had an RCA Ampliphase 50G transmitter. The output tubes were a pair of 5671s. They required 15KVDC plate voltage and 11VAC @285 amps for the filament. They needed 1800 cfm of airflow for cooling, were 25" high X 17" wide and weighed in at 228 pounds. I never had to change one, but there was a special lifting device in the storage room in the event that became necessary. The power supply cabinet had huge mercury vapor rectifier tubes that had a purple glow and changed in intensity with modulation. One time a tube in the oscillator section of the exciter went bad and we were putting out spurious signals across the AM band. I was on duty and started getting calls from other stations that something was wrong. I put the backup transmitter online and eventually found the problem in the oscillator section.

[@MrCarlsonsLab]

Thanks for sharing that! Interesting story.

[@Splungers]

I patiently await the unveiling of this tube- mounted in a Delorean!

[@toruscore]

He will be going to be having had done that in no time

[@mikafoxx2717]

Collaboration with Applied Science? Between the two, and the DeLorean, they could make it work.

[@nilo70]

Time travel 😮

[@orbitingeyes2540]

1.21 Gigawatts... well, that's about the total input power in roundly exaggerated numbers. 😂

[@Splungers]

@@orbitingeyes2540 I think Mr. Carlson's safety goggles were a tribute to Dr. Emmitt Brown.

[@kaysonntag74]

Some time ago I built a vacuum tube Tesla coil. With the largest tube in my inventory at the time, a Russian GU81M. The result was more of a “plasma flame” generator than a Tesla coil. When switched on, a plasma flame about 10cm (4") long ignited at the tip, causing the electrode to melt and drip to the ground within seconds. The operating frequency was about 3MHz. The GU81M requires “only” a fraction of the heating power of this tube here. At that time I heated the GU from a halogen transformer (toroidal core, 12.6V/18A). The anode voltage came from 2 microwave transformers with a two-way center-point rectifier with 4 capacitors from microwave ovens as filtering. When I switched on the anode voltage in the workshop, my PC crashed immediately and the TV went off two rooms away. The neighbor's TV showed a black picture and a loud 100Hz hum came from the loudspeaker. Thankfully, this was only temporary. After switching off the anode voltage and restarting the devices, everything was ok again. After this experience, I disassembled the device. It could have turned out differently. This is simply not a suitable toy for men in a densely populated environment. Not to mention the legality.

[@GeorgeWMays]

This will be great around Christmas time with friends and family all snuggled around the tube to stay warm this Winter.

[@allancopland1768]

At work we used a radio frequency dryer for sewing thread. It developed 30KW of RF at around 27.125MHz in the CB/ISM band. It was water cooled with the anode strapped to ground and the heater cand grid circuiits 'floating' negative with respect to ground. .A BIG triode that had a heater rated at 10V@240Amps. It was a BIG metal cased triode. I can't remember the anode voltage bit it was many KVs. One day, one of the hoses supplying cooling water came adrift spraying the RF deck with water (demineralised!) . The results were quite spectacular and the valve was destroyed pretty much instantly. The oscillator was a simple free-running type. Amazingly for me at least, I couldn't detect any RF leakage at all using my Kenwood R2000 HF receiver placed near the metal cabinet when the machine was running. The internal RF screening was superb with a lot of finger-stock and brass brush seals.. It was a carousel type dryer with the RF fed into a chamber at the rear of the machine to dry the thread which was wound onto 'cheeses' and stacked vertically in threes, with teflon spacers between them and a teflon top cap.. Vacuum was applied as the drum carrying the 'cheeses' entered the drying chamber which helped to force water out. 30KW of RF did a great job of drying the thread! When it failed, replacing the dead triode was interesting. The new triode arrived in a large wooden crate packed in straw. Ww used a forfkift truck to lift the crate over to the machine where we unpacked the valve and shoehorned it into the machine using the forklift truck.. These big transmitting valves are designed to be repairable. Thay can be taken apart and refurbished. I never did find out how much the new triode cost, but was glad the company was paying for it.

[@bobdeverell]

A long time ago I was a tech looking after a critical computer system using hundreds of valves. (tubes). We understood that the thermal shock of powering on and off the heaters is what reduces the MTBF of tubes. Best practice was to leave the heaters on all the time, but if we had to power off the heaters then slowly reducing the power was as important as slowly ramping up power. Nice to see Mr Carlson following this.

[@jwilli2460]

12 kv!! Mr Carlson, I'm a NERC certified transmission operator for a Midwest power company. I started in distribution. Most of our distribution lines are 12kv phase to phase, 7.2 phase to ground. The thought of you putting 12 kv on that tube in your shop gives me the willies!! I love your videos. When I was a teenager, I wanted to have your knowledge of electronics. Keep up the good work and be careful!!!!!!

[@stargazer7644]

I guess you had absolute heart attacks back when we all had TV sets in our living rooms with 20-40,000 volt power supplies in them.

[@vvdvlas8397]

12kV DC

[@piccalillipit9211]

I used to make tube amplifiers - I stopped when I gave myself a 485V DC shock. I figured ADHD and high voltage just dont mix well

[@stevebabiak6997]

@@stargazer7644 - there is a HUGE difference in the output power of the CRT anode supply and the voltage needed to drive that transmitter tube. Yes, in both cases the voltages can be lethal, but the power that will be supplying that transmitter tube is higher risk.

[@bofor3948]

@@stargazer7644 I have made mistakes fixing old TV's and felt the eht (25Kv) off the cap of a CRT. Makes you hop and probably not good for a weak heart, but no real current capability via the tripler and eht rectifier. A little more painful than a car ignition jolt. If Mr C puts 12Kv on the anode of that tube it can pass 1.5A. You won't say ouch if you get across that. You will pass a killer current in no time at all. Only the really old TV's which derived the eht 10kv or less directly from a transformer winding could pass enough current to be potentially lethal. Those tests if they involve high anode voltage and current capability should be setup behind a faraday cage in what we called a rubber room.

[@MichaelLloyd]

I probably never would have known a tube like this existed much less witnessed the filament light up if not for you Paul. I really enjoyed watching the process. Thank you.

[@MrCarlsonsLab]

Glad you enjoyed it Michael!

[@rocketman221projects]

That's still a little tiny tube. The big tubes were used in shortwave transmitters that put out 1MW or more.

[@rocketman221projects]

@OldWrench59 Search for pictures of the Eimac 8974. It's a big tetrode that takes over 20kW just to light up the filaments. It's surprisingly small for a tube that can put out over 2MW of RF.

[@RaymondLau-u7x]

This is one of the the BEST channels on all of You Tube.

[@MrCarlsonsLab]

Thank You Raymond!

[@larsch6529]

What did Mr Carlson do for a living before producing KZbin videos.This guy seems to have a vast amount of electronics knowledge. Thanks Mr. C.

[@gn1656]

And $$$$ 🤪

[@SidebandSamurai]

Wait. My lights dimmed when he lit that off. This is awesome thank you very much. I can't wait for the next electronics class

[@dansteel9873]

When I watched this the first time there was something I didn't like about this guy that I couldn't explain. But after watching 2 episodes I really like it and I'm hungry for more. Right on Mr Carlson. I need more. I'm retired after 29 years in broadcasting and I still want to learn more because guys like this make it fun to learn. Two thumbs up and bravo.

[@MrCarlsonsLab]

Thank you for the kind words!

[@rodrickbourque]

Great video! I see a Marconi 2955! I was gifted one of those but with a bad flyback. Instead of hunting down a flyback, I did the LCD conversion. I just used it today actually. Re-aligned the front-end of a Tait T835-20 receiver module converted from VHF high to 136-148. I broke my first couple RF slugs. Lesson learned! Fortunately I found some replacements! 73 from VE9 land!

[@jcramond73]

Experimentation with 14000 Watts of pure fury ! Paul, you have outdone yourself 👍

[@poro666]

I'd like to visit such a great laboratory;)

[@TheElectronicDilettante]

My wife is on me all the time for the electric bill being high when I run a few 3d printers and my big screen from time to time. I can’t imagine what your power bill could be. Definitely gonna do my part on Patreon though I doubt I’ll put a dent. I wouldn’t be surprised if you had your own hydroelectric system or geothermal operation. Thanks for all you do for those of us still learning, it’s more helpful than you know.

[@nikolatesla1358]

I like how You never treat People condescendingly You are a Fantastic Teacher and We all enjoy Your Projects which I could have been an assistant with You, Great projects and learning experiences. Thanks Mr. Carlson

[@MrCarlsonsLab]

You are so welcome!

[@olduhfguy]

As a former Gates Radio employee these types of tubes (vapor and forced air) were fairly common. They were impressive !

[@MrCarlsonsLab]

I still love my old BC-250GY!

[@Slugg-O]

Dr. Frankenstein would be proud! Thank you for your videos, and for having the absolute best tech channel on the net.

[@michaeldeloatch7461]

Felicitations for a fabulously fulfilling filament fire up. The suspense was palpable as you slowly turned the big vice grip handle. Now I can't wait to see what amazing things you will do. I commend you for wearing personal protective gear.

[@shaunsiz.itsbetterbytube2858]

A standard linear valve for a Italian QRP CB Operator lol

[@toruscore]

beautiful signal my friend

[@Lordbl4]

@@toruscore 58-59 TY 73

[@neonhomer]

Or just a fraction of the power the guys on 3950 run....

[@Wtfinc]

HAHA! Amen! If i had one id try. Had to settle for quad GU-81Ms instead. They are just barely manageable and that’s being optimistic lol.

[@edwatts9890]

​@@neonhomer: Or Channel 6 on 11 Meters. 10-4/s

[@ralfkruse7565]

I was once putting a Cellphone transmitter in service in the station building of a 25Kw AM station. The transmitter was next door. After lunch break, the door was open, but no one was inside. I took a look, and the modulator cabinet and transmitter cabinet was open. The same big glass tubes in both( 25cm diameter and about 40cm high) The modulator run on 6kV and the tx final on 10kV. Then the station technician came in, got pale when he saw me . ( he came from a toilet break). Thank God, you are alive! After questioning him a bit ,i showed him the cellphone station next door, which ran only on 48V. Less dangerous! Great videos, Mr C. 73, F1VEL ex DB3YZ

[@MrCarlsonsLab]

Thanks for sharing your story!

[@anandarochisha]

Fantastic. Biggest Variac that I have ever seen. Very unique Video !

[@MadScientist267]

Yeah I thought I had a decent beast over there in the corner... that thing is absolutely massive. But when you need it you need it... And "warming up" 🤣

[@mrnmrn1]

We have 'one' of these at work, but in 3-phase configuration for 3x230V, the sections are 115V each, that means a tower with SIX of these on top of each other with a common shaft, driven by a motor. Now *that* is a beast. IIRC it can do 3x230V, about 100A per phase maybe. I don't remember the brand, but it's US made, some time in the '60s or '70s.

[@MadScientist267]

1200W for filament, 600W drive... 14kW output. The highly efficient vacuum tube is not to be underestimated 🤣

[@samuellourenco1050]

It is more efficient than an op-amp.

[@chunkycheesemonkey99]

Source?​@@samuellourenco1050

[@stargazer7644]

Don't forget about the 18,000W plate power. 1.5A at 12,000V.

[@orbitingeyes2540]

​@@stargazer7644that's only 6 microwave transformers in series. 😂

[@CarlosSilva-gc8ny]

Un tubo de vacío nunca es altamente eficiente, como maximo llegará a un 30-40% de eficiencia, lo demás se pierde en calor.

[@jaroslawgrajdek3572]

"Wall" behind You...very impressive.

[@aaronwarman71]

That's really good practice to start the tube filament off from 0v and build the voltage up slowly, especially if the tube hasn't been used in a long time or is of an unknown status, great vid.

[@XNLFutureTechnologies]

Very interesting to see that tube 'come to life', very neatly done👍🏽

[@mikebiron7339]

Fascinating departure from your normal videos! It was very interesting to see you outside your normal box\bench out in the garage with a cobbled together experiment. Thank you. I enjoyed this video.

[@MrCarlsonsLab]

Glad you enjoyed it!

[@mikebiron7339]

@@MrCarlsonsLab For one awesome year, I was gifted the job of teaching middle school kids basic electronics. The art of teaching as you do is not easy, but if you love it like you and I its very fun. I can see your enthusiasm as I had too. I taught my students the basics and we built things not on any list or required instruction. I got to see these kids open their minds to possibilities and ideas, where in the beginning of the class there were none. I hope you keep the joy of electronics going for all to experience.

[@jlev505]

My favorite channel on KZbin! With the best teacher on KZbin! Thank you Mr. Carlson for your sharing of knowledge and excellent way of teaching. You inspired me to read and read and read even more about electronics. I now repair audio amplifiers and any home/ car audio equipment. I also work at a board repair shop during the day repairing oilfield automation equipment. Thank you for making electronics addictive. You’re a great and entertaining teacher. Have a blessed day, sir.

[@mikefinn2101]

That was amazing well done Paul. Never seen this big a tube ever.

[@harrymeyer5895]

I had a wood products company in the 90’s. I was able to find an old high frequency gluing machine and it had a huge tube similar to the one you have. I could cure 4 inch thick butcher blocks in a couple of minutes!

[@richardross3815]

I remember those machines.

[@beswald1878]

This is the best channel, great mix of education, cool old electronics and pure mad scientist! Love it!

[@MrCarlsonsLab]

Glad you enjoy it!

[@mxslick50]

I seem to recall a video with a high power AM transmitter using this same tube. They emphasized the importance of cooling, ramping up filament current slowly, and most importantly, never applying plate voltage until after the tube was fully warmed up. They also mentioned the very high cost of these tubes.

[@VincentGroenewold]

Totally awesome, that this actually survived all these years is amazing. I guess it didn't go through many hands then, likely being in a Mr. Carlson's look-a-like lab before. :)

[@throttlebottle5906]

somewhere in the world, there's likely some of these still in daily service!

[@fuloplehel]

Great video, I'm happy to see the tube is working, no magic smoke. Great projects are coming. 👍👍👍👍👍

[@MrCarlsonsLab]

Thanks 👍

[@mehamrdio6173]

Thanks!

[@MrCarlsonsLab]

Thank You!

[@cafemolido5459]

Vacuum tube, such a SIMPLE yet GENIOUS invention. A lot of R&D went into it for sure.

[@anthraxrocks2003]

Studied electronics in high school wound up being a carpenter still have a facilitation with electronics thanks for the great videos

[@dennisisham1989]

On the edge of my seat waiting for the smoke and flash! Glad it works. Can't wait to see the experiments.

[@michaelcalvin42]

That has got to be the spiciest piece of glass I've ever seen. I'm excited to see what experiments you have in store for it!

[@richardgoebel226]

If you are following along at home you are doing so at your own risk. (causing a power outage)

[@josephcooksley3219]

Very true or breaking the Bank with your Power Bill

[@aetch77]

Not at this stage. 22V * 56A = 1.176kW, that's less than half what my kettle pulls (2.5-3kW)

[@JeffDeWitt]

A few lifetimes ago, like in the mid 70's, I was able to take a tour of the transmitter building from our local 50,000 watt AM station (WPTF). These final amp tubes were HUGE, I seem to remember them being almost as tall as I am. It was cool seeing this big old tube fired up and what all goes into it... that's a LOT of power for just the tube heaters! Great stuff!

[@ka1wht]

So much fun to watch, that had an element of suspense! I maintained AN/URT-23D HF transmitters while serving in the U.S. Navy and remember working with the high voltage Eimac vacuum tubes. I am also a ham~KA1WHT. Looking forward to seeing more!

[@Pootycat8359]

What a cute, little transmitter tube! In the 1980s, I did the maintenance & repairs for a Harris MW-50A 50 KW AM broadcast transmitter. The PA final was an Eimac 4CX35,000, and the plate P.S. was 24 KV. The xmttr came with a screw operated jack, for putting the tube into, or removing from, its socket. Of course, engineers who have worked on 500 KW shortwave transmitters would consider that 4CX35,000 to be puny.

[@stevehodder1]

Damn, I thought the 4CX15,000 tubes we used at our naval radio station were big!

[@Pootycat8359]

@@stevehodder1 At the time I was responsible for the care & feeding of that xmttr, they sent me back to Illinois, to attend the Harris "Transmitter Training Course," for that model. While there, I learned that they had built a SW transmitter for Saudi Arabia, which had a power output of 1 MEGAWATT. I don't know what kind of PA tubes it used....probably a bank of them, in parallel.

[@optimisticpessimist484]

Very interesting. I maintained an Harris MW-5A for a station in Kokomo. Same basic transmitter, but, a lot smaller, used a 4CX3000A as a switch tube and a 3CX2500F7 for RF final. Plate efficiency was an astounding 92%! Made beautiful audio.

[@chrisbrooks6697]

If Mr. Carlson is wearing PPE, you know it's about to get REAL!

[@brianwood5220]

WOW that's some tube, Paul. Thanks for sharing.

[@brianclimbs1509]

I found this unreasonably exciting! I must say that you brought it up and down faster than I would have dared… I would have waited a long time for it to reach thermal equilibrium. You should make a driver circuit for a cyclotron if you can’t get some special permission to run a high powered MW or shortwave station.

[@leonardpeters3266]

That is just amazing. Holy moly the power output 14,000 watts. I must admit I would prefer you to be operating that variac behind a 3/8 inch piece of Lexan. You make my heart beat a little faster when you're that close that glass MONSTER!

[@donl1846]

This was great Professor Carlson. I even felt like a mad scientist just watching this, lol. Thank you for sharing this gem of a tube!!!!

[@MrCarlsonsLab]

Glad you enjoyed it!

[@fullwaverecked]

Mr. C goes sport fishing. Awesome video!

[@MrTylerStricker]

It's really interesting to see how they accomplished the thermal management here. You can certainly see the roots of modern day electronics cooling and thermal solutions.

[@larryowens2859]

So very interesting, thank you so much for sharing this Larry Owens

[@michaeldeloatch7461]

Incidentally, the only real surprise of this episode: @5:05 I was sure Mr. C. was going to say, "and I have measured and this custom battery connector by coincidence fits the filament pins of the 892-R precisely, so I will be plugging it right in"

[@ronhonick549]

I can understand powering the filament and will be eagerly awaiting to see how you're going to test the rest of the tube. Great video!

[@kevt5090]

This is really cool. The biggest tube I have seen not in commercial service.

[@Ragnareaver]

Wow, what a monster, but a beautiful one. Thank you sir for this video!

[@MrCarlsonsLab]

My pleasure

[@happycamper5213]

The biggest tube I worked with was a 4CX250B uhf amp. It needed a screaming fan to keep it cool.

[@MrBtcruiser]

Last time I saw a tube like that was at a tour of a local 50 KW clear channel AM station when I was in technical college.

[@basshorseman998]

Well now, in the 70's, I worked in a radio station that still used tubes so, this is fun for me...Thanks

[@MrCarlsonsLab]

Glad you enjoyed it

[@johnsampson1096]

It appears that four of these tubes could operate a 50kw AM station! WBZ 1030 is a clear channel out of Boston that reaches half way across the USA. It is now all talk and info, but in the sixties a top 40 AM power house. Thanks for the exhibit, Paul!

[@JCWise-sf9ww]

Just Awesome! The filament alone consumes as much power as a portable electric heater or a hair dryer does!

[@Greg-et2dp]

Mrister Carlsons lab 73s to you and your wife my friend

[@davidbauer8800]

Mr. Carlson wins the biggest Tube on KZbin award!

[@Michael_Michaels]

This test reminds me of Photonicinduction experiences! Crazy cool stuff the guy did! Keep on the good work! Thank you!

[@onesandzeros]

Yeah I was thinking of that guy too. Just need some capacitors like paint cans and a mercury rectifier or two. Oh and just set it up on the carpet in your living room. He hasn't posted in a few years, I hope he is well.

[@yodab.at1746]

​@@onesandzeroshe is ok. He appeared recently on another channel swapping some parts.

[@qzorn4440]

The design engineers for high power vacuum tubes in the early days "20s-30s" are amazing people. ✨😎 Thank you Mr. Carson for a great video.

[@nathkrupa3463]

Great video Mr Carlson sir you are awesome ❤😊thanks for sharing this video sir

[@MrCarlsonsLab]

Glad you enjoyed it!

[@solarbirdyz]

Now that had some suspense. That was fun. Also, _wow_ that variac. Looking forward to the experiments! :D

[@W1RMD]

I love the way this channel is heading. Thanks and that makes a great room heater. In winter you're heating the room anyway so no power is "wasted". Take care!

[@Greg-wq4dj]

I really enjoy the demos of lesser-known industrial electronics and components. After experimenting with kv plate voltage and current, perhaps you could demo the other definition of ‘grounding’ when Mrs. Carlson sees the power bill!

[@JugSouthgate]

892R has a pure tungsten filament - that's why it uses 1200+ watts and glows so brightly. Slowly bringing up the voltage and current is necessary because the tube specifications say the filament current must never exceed 120 amperes (!). The 1964 Newark catalog shows the 892R priced at $425 US - about $4300 in today's money. They were so valuable that burned-out ones would be sent back to the manufacturer and rebuilt. Tube data on the 892R and its water-cooled version 892 from several manufacturers is on the internet in several locations. Take a look - they're impressive.

[@va7da]

Great project Mr Carlson.

[@MrCarlsonsLab]

Thanks Dave!

[@MattHeere]

I had the good fortune to tour the KDKA (AM radio) broadcast transmitter site back in the 80's. The tube finals that powered the 50kW Westinghouse broadcast transmitter are works of art. That site is it's own distribution substation with multiple transmission feeds to keep it alive too.

[@kozkoz7776]

by far the best electronics teacher on youtube fascinating stuff 🌠

[@glennk1931]

This is so interesting to watch, as all of Me Carlsons’ videos are.

[@tpobrienjr]

Very nice. You saved me from the temptation to light up my Eimac 527A, which draws 135 amps at 5.5 volts. I am content to light it up with an UV flashlight, which makes its seals glow a nice greenish yellow (Uranium glass)

[@MichaelWizard-dt9ve]

This is so cool! I love stuff like this. Glad it worked out.

[@markshogan2642]

Back in the mid 1950s the Pennsylvania Railroad purchased new electric freight locomotives to operate on their electrified divisions. They had water cooled rectifier tubes in them to convert the 11,500 volt 25 Hz AC line power to DC then to transformers to run the 600 volt DC traction motors. Yes, water cooled tubes on a freight train traveling at 50 mph. They lasted in service for about 30 years. The tubes were massive.

[@markshogan2642]

The locomotives lasted thirty years, not necessarily the rectifier tubes.

[@johncampolo2177]

That is an impressive vacuum tube. My dad was a transmitter engineer and worked at AM 50kw stations here in the stares. He took me to work some days in the 1980s, and I remember some transmitter sites around NYC such as WABC, WNEW, and one other I can not remember. I saw some really big modulator and final tubes in those transmitters. Not sure if your tube was there.

[@SeenOrHeard]

Makes me want to break out my 4CX5000A and build a resonating cabinet for it. I remember maintaining a transmitter that used a set, with individual filament transformers rated at 150 amps. Mains power was stepped down to 5 volts, and the tube took whatever current it needed. They center-tapped the secondary and tied it to ground for the valve circuit. Running that thing was a blast! 25,000 visual watts

[@ivarlarsen6045]

Man, that is awesome. Reminds me of the channel Photonicinduction

[@ScottRemington]

Oh. My. God. This is so unreal! Using a massive battery charger to drive the filament and a Variac controlled with a pair of ViceGrips! I'd love to see what that "filament" looks like. A coil of 10 ga solid core??? LOVE IT and can't wait to see what "tests" are being devised! Oh, just to have his source of "junk"...😲 I'm just glad I don't have his electrical bill!!😳

[@BillGraysons]

I remember seeing a huge vacuum tube made by Eimac. I saw it when I visited a VOA transmitter site here in the USA. It was not in service. It was on display. The tube was a 8974 and made of metal and ceramic. It has a height of 23.75 inches, a diameter of 17.03 inches, and weighs 175 pounds. It contains two directly heated filaments rated at 16.3 volts at approx. 1300 amperes for both filaments. The anode is designed to dissipate 1.5 MW. The tube may be operated as a class C amplifier where a single tube with an anode voltage of 22.5 kV DC can provide up to 2,158 kW of RF power!!

[@douro20]

That was the largest transmitting tube ever produced. Some of them were used in particle accelerators. Continental Electronics apparently made transmitters using these tubes which were used in wide area AM broadcast at up to 1MW- they use two 8974s, one of which served as the modulator.

[@bigman55434]

That battery charger. Gould batteries was based in Mendota Heights, Minnesota. They became GNB batteries, I think around the late 70’s, early 80’s. GNB moved their HQ to Mississippi around 1989. Exide eventually bought them, and went bankrupt about 15 or so years ago. My dad worked there his entire career.

[@MrCarlsonsLab]

Thanks for sharing your story!

[@jamesdye4603]

Glad the tube is still good, because now comes the experiments.👍👍

[@denisdespins1127]

Wow. I was sweating WITH you. Quite fun ! I've been told "you know you have arrived when you screw around with MASSIVE power and don't make any mistakes" peepeer's phrase...

[@peep39]

I desperately need to see experiments with that giant tube. Huge tubes and huge power supplies are where it is for me

[@besanit]

Big explosion get a lot of attention but I prefer big power being controlled, there is not much challenge in just releasing it

[@KeritechElectronics]

Nice job firing this baby up! Dwarves my Tesla ZD1000F transmitter triode, the biggest one in my collection, with 1kW plate dissipation and 250W on the heater. "You call that a vacuum tube? THIS... is a vacuum tube." That variac is by far the biggest one I've ever seen. You could try adding a motor with worm drive to it for remote control.

[@PeterDyall-bn7ut]

Wouldn’t it be fantastic to interview Paul’s mom!

[@guilldea]

Thumbnail alone is gonna bring new people to the channel

[@michaelcarey]

That's a very impressive tube Mr Carlson. I can't wait to see what you do with it in the future. I've got an old transmitter tube in my collection. It's an STC 4279-Z triode from 1955, made in Australia. 10V filament at 21 Amps. 2500V anode. The GI7B triodes in my rebuilt Yaesu FL-2100Z amplifier are tiny compared to this monster, 21.25" from tip to tip.

[@framefu]

I admire your courage, you are a superhero!!!

[@egomezmx65]

oh man, that thing look mean and dangerous, this was a super exciting episod, like from an old Frankesnstain movie (its alive!). This episode really needed the "...you are doing so at your own risk..." and I'm sure you had the fire extinguisher near by. Thanks a lot Paul!

[@edwatts9890]

I am building a 160 - 10 Meter amplifier with a pair of grid-driven 4-1000A's in class A, push-pull. It won't be super efficient; but I make my own electricity, and I absolutely love the glow of glass bottles with cherry-red plates!

[@JohnShalamskas]

Push pull is not class A. It's probably class AB. Neither tube conducts over the entire cycle.

[@HD63C09EP]

Thank you so much.

[@MrCarlsonsLab]

You're welcome!

[@stevegomez3505]

In the 1940's the RCA BTA-5F 5 KW AM broadcast transmitter used 3 892-R tubes, 2 push pull AF modulator and 1 class C RF output tube. You could open the front panels and literally step inside.

[@robincross4625]

I worked for a station that had a BTA-10F 1947 10 KW transmitter. Four 892-Rs, two in the Final and two modulators. Kept the building warm in the winter.