Hello all.
A naked picture tube. Monochrome. Have three. Want to power at least one to play with. No image, no raster, no deflection, no video signals to it. Just a beam dot on phosphor.

The pertinent portion of the donor schematic is :


The left top area with Q5520 can be ignored; I see no connection to the CRT. The right side CN9310 are just grounds.
That detail is:



Now for the good stuff:
CRT pins 6, 7 are heater filament - Take 6V
CRT pins 4,5,9,11 are grid 1 - take 1K to gnd ... I think
CRT pin 8 is cathode. Comes from the video output amplifier which I do not want to use.
CRT pin 10 is grid 2 - What voltage to apply ?
CRT pins 1, 12 whatever they are chassis grounded.
Whatvoltage or circuit should I apply to 'focus block' under CRT pin 1 ?
CRT anode ... Apply 10 to 20 KVDC from whatever circuit ?



CRTs look like :





Thanks for suggestions...

 

It appears that you already have all the information to do what you are describing. What is your question?

 

You need to apply an eht as said 15Kv DC to the final Anode, as well as the heaters, and a feed signal to the cathode,
Usually the eht is developed from the line output transformer which is also the horizontal scanning circuit.

 

hi Ext,
As Dodgy points out, Line scan for EHT, so no video signals to it. Just a beam dot on phosphor.
It is not going to happen.
E

 

With no deflection, wouldn't a focussed dot in a fixed position soon burn the phosphor?

 

hi,
Yes. also, I don't see any iron trap magnet.?
E

 

With no deflection, wouldn't a focussed dot in a fixed position soon burn the phosphor?

Yes it will be in the centre blurred unless it's focused, ..

 

Without the correct voltage on the cathode it is not likely that there will be any beam or any dot on the screen. AND those three grid connections would appear to be for the three grids, as a color CRT is shown in that side view that has no pin numbers, And those "ground connections" are for grounding the outside of the CRT, which is a very important part of the high voltage filter capacitance.
So it is rather unclear, because that schematic shows a color CRT with three electron guns, while the instructions describe a package with three separate CRTs , R,B, and G. Does the number of pins on each CRT even match the number shown in the diagram??

 

Thanks, fellows.

It appears that you already have all the information to do what you are describing. What is your question?

Questions are

* CRT pin 10 is grid 2 - What voltage to apply ?
* What voltage or circuit should I apply to 'focus block' under CRT pin 1 ?
* Would a simple animal like this work for anode supply ?
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Yes, a maybe blurred or not dot on phosphor that may burn a point is what am after. Not to display video nor implement deflection. I see two grids G1, G2.
The 'color' CRT pictorial at right is incorrect. Has to be some copy/paste from another schematic from a lazy tech writer just to show where the CRT grounding goes. Pins do match.

 

The focus is usually around 12Kv adjustable , the middle grid is around 8K (called A1) both of these are located on the line output transformer, and the g3 is grounded, the Eht voltage is positive 20Kv approximately,.

Search for a circuit diagram of a monochrome tv like a Nikkia baby 10 , this will give you an idea of how they work, the monochrome version doesn't seem to be available.

https://elektrotanya.com/nikkai_baby-10_k3910-01.pdf/download.html#dl