What is the smallest CRT that people here know of?

I would very much doubt it's a CRT. Probably a B&W LCD with a variable focus lens for those who need to wear specs.

Good luck with the fixing, though. If you do have to rip it apart to get to the screen, might as well have a crack at fixing the mechanism (if you can be bothered)

-mark

"mark jb"

** I think it very much is a tiny CRT.

There is one on my old Sony.

........ Phil

**You'd be wrong. CRTs were very common in old video cameras. In fact, they were prized above early LCDs, since they provided far better deatil, albeit in monchrome. **Nope.

--
Trevor Wilson
www.rageaudio.com.au

"Trevor Wilson"

** I just opened up the viewfinder part of my old Sony CCD300AU and had a peek.

Amazing.

A tiny CRT, about 56mm long, with a 5/6 pin plug on the base and a set of deflection coils around the neck covered in a ( tin plate ?) metal shield.

The phosphor screen is about 18 mm diameter, masked down to about 9 mm by 12 mm actual viewing area ( 14mm diagonal).

The B&W image is sharp as a pin.

........ Phil

**It may even be mu-metal. You never know your luck. **Yep. MUCH better resolution than the first generation LCD viewfinders. In fact, probably better resolution than the best current generation LCDs as well.

--
Trevor Wilson
www.rageaudio.com.au

Fixing? That wasn't really my intention. I was only interested more out of curiosity as to what was inside then fixing it. The parts in the mechanism are very tiny and hard to see and I'd more then likely lose them .

I have had to say bye bye to that side of my electronics hobby. I am finding the parts way too tiny most of the time even in kits to do anything with and its been hard to say bye bye to this..

Toshiba have an experimental 20" flat panel screen that has individual CRT's for each pixel - still in R&D at the moment, though they've shown it at one of the European Expos -- they hope it to be the successor to Plasma - cheaper and less juice and better picture contrast.

Colin

"bodgy"

Toshiba have an experimental 20" flat panel screen that has individual CRT's for each pixel - still in R&D at the moment, though they've shown it at one of the European Expos -- they hope it to be the successor to Plasma - cheaper and less juice and better picture contrast.

** So each ''CRT " is about 0.3mm diameter ???

Obviously there is no deflection system and no internal grid or anode structure so the title " CRT " is just a TAD misleading.

But if high speed electrons are striking a phosphor to make light ..............

....... Phil

sounds like a plasma to me........similar system...

On Wed, 07 Dec 2005 00:04:20 +1030, John put finger to keyboard and composed:

I once had to replace a faulty flyback transformer in a National VHS camcorder viewfinder. It had a monochrome CRT.

-- Franc Zabkar

Please remove one 'i' from my address when replying by email.

Matt said

:: sounds like a plasma to me........similar system..

Phil said

:: But if high speed electrons are striking a phosphor to make light

Well yes, I was on my way to bed when I typed that.

Toshiba & Canon using Surface-conduction Electron-emitter Display technology (SED) hope to have by 2007 50" displays of 1920*1080 contrast ratio of 100,000:1 at a rate of 75,000/month ---- I'm quoting from their blurb here, so some hypebole is to be expected.

The technology is similar to Plasma, but without using noble gasses.

The HT is supplied between two glass plates, with the low voltage electron emitter being in a 10nanometre slit that on one side has the phosphor.

A better description and nice drawings are at

and here for links to white papers.

tml

Off to bed now!

Colin

Ummm... I had the idea that plasma occurs in a gas, not in a hard vacuum. I'm sure that Phil can elaborate on the details.

Bob

How big is the FBT for a CRT that size?

"Lord-Data"

** It could be carried on a fly's back.

....... Phil ;- )

A plasma is an ionised gas. Kinda hard to ionise a vacuum.

Cheers Alf

On Fri, 9 Dec 2005 16:42:19 +1100, "Lord-Data" put finger to keyboard and composed:

Well, its p/n is ETF14L20B. The service manual has a scaled up circuit layout. Using the H&V oscillator IC (AN2510S) for comparison, I'd say the scale factor is about 4:1 which means the FBT's footprint would have been about 21mm x 16mm. In the exploded diagram the FBT looks about as high as it is wide, so my best guess is 21 x 16 x 16mm.

-- Franc Zabkar

Please remove one 'i' from my address when replying by email.