Solved Are CRT Tubes Tied To A Specific Voltage? (either 110V or 240V) - NO THEY ARE NOT

Martinmurphy30

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I think there's a lot of confusion going on here.....wasn't the original question about the difference in 240v Vs 110v monitors? A tube needs a high voltage to operate, this comes from the chassis which operates on 110 or 240v (give or take). The tube doesn't care what the mains voltage is, it's the chassis that is matched to the tubes high voltage, drive levels, yoke impedance.....etc... that's my understanding at least, how would anyone have a definitive list of chassis, tubes and readings? The question is the problem here, no, there is no difference in mains requirements for a tube, the chassis tied to the tube is what makes it work.
 

Retroman839

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there is so much you need to know, where do you start
tools you will need-multimeter, inductance meter and bench meter(unless your multimeter is something like a fluke 87v) and probably a hv probe
bench meter to read and match heater voltage, inductance meter to compare and read yokes, same with multimeter for impedance, hv probe to check eht is within spec
then you have tube base pinout and neck size, whether yoke has pincushion fins and whether chassis has adjustable pincushion circuit, then you have all the different type of connectors and input voltages and frequencies

so no its not simple but if you have a particular chassis you want to replace you could probably find a later direct replacement by doing an internet search
Very nicely and Compactly summarized , thx 4 sharing 👍.

In Spain they say “ it’s an open mouth that catches the flies “

As a person who has made more than his fair share of social gaffs I have learned the hard way to think about how my words are perceived “


I’m still looking for these pin Cush fins 🧐. .🦈. to ident pin Cush or no pin Cush,
Then I will get a HV probe ..

I’m lucky that I have struck up some good comms with my local tip and I’m donating to charity for access to the crt’s that are disposed of by public,

So I’m slowly matching 3 at mo
Samsung Plano 29 - pentranic ch- 28 .. fine except screen momentarily jumps with white screen in game footage .
Fidelity / vídeo colour - mtc 900E
And a tosh , with mini kneck
Still need to read yoke impeadance inductance as soon as life allows me to

Between balancing houses on sticks
IMG_2665.jpeg

Ps tb2000 - I have pm you regarding the mtc 900E😉
 
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eliotcole

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Excellent. 🏆
So then, No ... a tube is not tied to a specific voltage.

Thanks, @Martinmurphy30 . :)
I think there's a lot of confusion going on here.....wasn't the original question about the difference in 240v Vs 110v monitors? A tube needs a high voltage to operate, this comes from the chassis which operates on 110 or 240v (give or take). The tube doesn't care what the mains voltage is, it's the chassis that is matched to the tubes high voltage, drive levels, yoke impedance.....etc... that's my understanding at least, how would anyone have a definitive list of chassis, tubes and readings? The question is the problem here, no, there is no difference in mains requirements for a tube, the chassis tied to the tube is what makes it work.
 

eliotcole

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Hiya, @yoganuggy, thanks for the reply! ... That said ... even after a brief StartPage search I am not really sure what that means with regard to whether the CRT tube is tied to a specific voltage, sorry, mate.
If you need to re-gun your CRT eliotcole, here are the steps.

have fun!

( ... plus, I don't allow random videos to play because of YouTube privacy overreach ... )

Either way, I was just after whether or not a tube is restricted to a specific voltage, and I'm happy to report that @Martinmurphy30's response states that it is not! :)
 

NivagSwerdna

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FWIW CRT tubes certainly are specific to different voltages due to their geometry. A larger tube requires a larger anode voltage due to the area of phosphor being illuminated being larger, to get the same brightness a larger surface area will require a larger anode voltage to accelerate the electrons faster.
This is why small tubes, like mine require small fly backs. A very small tube, eg a oscilloscope will be say 5kV but a large arcade monitor could be 30kV with mine somewhere in the middle.
The voltage needs to be matched between chassis and tube otherwise it will ruin your day.
No idea if that was your question though.
 

eliotcole

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My question was:
Are CRT Tubes Tied To A Specific Voltage?

Turns out the below was wrong.
----
Which I confirmed with the following, @NivagSwerdna, in my OP ... which kind of asks the same thing but in an 'opposites' fashion, incase the titular question was unclear:
To keep things simple ... a yes or no question
CAN ANY TUBE TAKE ANY VOLTAGE?
If the answer is 'sometimes' or 'it depends' then that's classed as 'No' in this particular question. 🙂

I would assume that one would need to ensure that a tube can take a certain voltage.
So, I will change the title to indicate that they ARE voltage specific, thanks, @NivagSwerdna !
 
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NivagSwerdna

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It's an ambiguous question though as there are multiple voltages to consider... With a little help of my imaginary friend...

CRT Parts and Their Driving Voltages

A Cathode Ray Tube (CRT) is a vacuum tube that uses an electron beam to produce images on a phosphorescent screen. Below are the main parts of a CRT and the typical voltages that drive them:



1. Electron Gun Assembly
Generates and focuses the electron beam.
  • Heater (Filament) – Heats the cathode (~6.3V AC or DC).
  • Cathode – Emits electrons when heated (~0V to -100V, relative to G1).
  • Control Grid (G1) – Controls beam intensity (-20V to -100V relative to cathode).
  • Focusing Anode (G2) – Accelerates electrons (200V to 600V).
  • Accelerating Anode (G3) – Further accelerates electrons (1kV to 25kV).

2. Deflection System
Steers the electron beam across the screen.
  • Electrostatic Deflection (oscilloscopes)
    • Horizontal & vertical deflection plates (100V to 3kV).
  • Electromagnetic Deflection (TVs/monitors)
    • Vertical coils (50V to 150V), Horizontal coils (1kV+ pulses).

3. High Voltage (HV) Anode
  • Connected to the conductive coating (Aquadag).
  • 10kV to 30kV (higher for larger CRTs).
  • Generated by the flyback transformer in TVs/monitors.

4. Phosphor Screen & Shadow Mask
  • Phosphor coating glows when struck (no applied voltage).
  • Shadow mask (color CRTs) is grounded to prevent charge buildup.



Typical CRT Voltages Summary
PartVoltage Range
Heater (Filament)6.3V AC/DC
Cathode0V to -100V
Control Grid (G1)-20V to -100V
Focus Anode (G2)200V – 600V
Accelerator (G3)1kV – 25kV
HV Anode10kV – 30kV
Deflection Coils50V–150V (vert), 1kV+ (horiz)



Notes:
  • Black & White CRTs use lower voltages than color CRTs.
 

eliotcole

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Sorry, I don't understand, @NivagSwerdna ... I thought that you had just said that a CRT tube will be built to utilise a specific voltage, for example, either:
110v
or
240v

Are you now saying that this is not the case, and that any CRT tube can receive either 110v OR 240v?

If so, I will change the answer to the yes / no question as your previous answer indicated the opposite to me.
It's an ambiguous question though as there are multiple voltages to consider... With a little help of my imaginary friend...

CRT Parts and Their Driving Voltages

A Cathode Ray Tube (CRT) is a vacuum tube that uses an electron beam to produce images on a phosphorescent screen. Below are the main parts of a CRT and the typical voltages that drive them:



1. Electron Gun Assembly
Generates and focuses the electron beam.
  • Heater (Filament) – Heats the cathode (~6.3V AC or DC).
  • Cathode – Emits electrons when heated (~0V to -100V, relative to G1).
  • Control Grid (G1) – Controls beam intensity (-20V to -100V relative to cathode).
  • Focusing Anode (G2) – Accelerates electrons (200V to 600V).
  • Accelerating Anode (G3) – Further accelerates electrons (1kV to 25kV).

2. Deflection System
Steers the electron beam across the screen.
  • Electrostatic Deflection (oscilloscopes)
    • Horizontal & vertical deflection plates (100V to 3kV).
  • Electromagnetic Deflection (TVs/monitors)
    • Vertical coils (50V to 150V), Horizontal coils (1kV+ pulses).

3. High Voltage (HV) Anode
  • Connected to the conductive coating (Aquadag).
  • 10kV to 30kV (higher for larger CRTs).
  • Generated by the flyback transformer in TVs/monitors.

4. Phosphor Screen & Shadow Mask
  • Phosphor coating glows when struck (no applied voltage).
  • Shadow mask (color CRTs) is grounded to prevent charge buildup.



Typical CRT Voltages Summary
PartVoltage Range
Heater (Filament)6.3V AC/DC
Cathode0V to -100V
Control Grid (G1)-20V to -100V
Focus Anode (G2)200V – 600V
Accelerator (G3)1kV – 25kV
HV Anode10kV – 30kV
Deflection Coils50V–150V (vert), 1kV+ (horiz)



Notes:
  • Black & White CRTs use lower voltages than color CRTs.
 

Alpha1

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@eliotcole I think you're getting confused between input voltage to the chassis which to be fair is either 110 or 240 volts, which is aligned to country voltage I.e the US etc for 110 and most of Europe and Australia etc for 240, over the voltage that a tube requires to power it sufficiently from the high voltage transformer or flyback as it's otherwise known.

As has been stated, the flyback will have a sufficient KV to power the tube based on essentially the size of the tube.

The chassis on the other hand will take the input voltage such as the voltage of the country of origin ie110 or 240 and then power the components on the chassis which includes the high voltage transformer AKA flyback.

Neither are mutually exclusive, the chassis is just converting the voltage in the country of origin to power the components on the said chassis. It doesn't matter if it's 110 or 240 to power a tube of any size for a television or arcade monitor as the chassis will do what it needs to do to sufficiently provide the high voltage transformer with the power it needs to operate optimally.

I hope that helps.
 

eliotcole

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I am not talking about the chassis or anything. I am asking if it matters what voltage is used for the CRT tube itself.

If the tube does not care about voltage, then the answer is 'no' :)
If I'm understanding this right and you're talking about the chassis and mains voltage stuff, then yeah, nothing to do with the tube itself.
A few of the CRTs I have can actually take universal voltage from 100V to 240V
 
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