WHY so few "other brands' left out there?( Admiral, Sylvania , Philco, etc)

[Jon A.]

The trouble with weak Sony CRTs, aside from their not taking rejuvenation is that they can only be replaced with other Sony CRTs. Lots of RCA-supplied CRTs in sets of other makes, even the rotting Canadian-model Hitachi I picked up had a RCA CRT and yoke, which I still have along with most of the other parts.

[etype2]

Originally Posted by Jon A.

The trouble with weak Sony CRTs, aside from their not taking rejuvenation is that they can only be replaced with other Sony CRTs. Lots of RCA-supplied CRTs in sets of other makes, even the rotting Canadian-model Hitachi I picked up had a RCA CRT and yoke, which I still have along with most of the other parts.

Why would anyone want to put a non Sony CRT in a Sony set?

The Trinitron one gun with three inline cathodes is what set Sony apart from all others with its superior focusing and lack of a need for convergence adjustments.

[andy]

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[etype2]

Originally Posted by andy

I think he just meant that it's impossible to do, unlike other brands which all use interchangeable CRTs (eg. you can put a Zenith CRT in a Sylvania TV, or a GE CRT in an RCA TV).

It's a myth that Sony's don't require convergence. Trinitrons are less complicated to converge than a delta gun, but more complicated than a typical in-line gun.

I was thinking about the time when the Trinitron was first introduced. Decades later, other manufactures caught up to a certain degree but could never duplicate the Trinitron until Sony's Patent expired in 1996.

The Trinitron only requires 6 picture tube adjustment controls compared to 24 in the typical shadow mask of that period. The cathode are in one plane as opposed to different planes in the shadow mask system of that time period. The Trinitron uses no convergence yoke, instead 4 electrostatic convergence plates. Vertical mis convergence is impossible in a Trinitron tube, therefor vertical convergence control is not required. Only small horizontal corrections are needed left and right, also the vertical stripes make beam landing errors less sensitive to the Earths magnetic field.

[andy]

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[rca2000]

Don't forget the RCA -based tube with in-lne gun and the "magnetized tape" band over the end of the gun--for convergence. These usually required NO convergence adjustments--that tape did it all, set from the factory. Those tubes were not too bad , either. They hold up a LOT better than the JUNKatron tubes do !! JUNKatrons had an incredible picture...for a short time..before they died and could NOT be brought back. NOT really worth the premium Sony charged for them, often with a shitty, hot chassis to boot.

[sampson159]

i second that rca2000.those crts held up very well.a 23v and a standard 25 are the same.the reason the sylvania wouldnt fit right in the zenith was the corklike tape on the side of the crt mask.have to remove it so the crt will set in the mask perfectly.been there too many times not to know.a sylvania 25vdmp22 in a flat chassis zenith will make the ultimate set.the greatest chassis with the finest looking crt.done it once and had a mindblowing set that went with the ex.hope the other guy enjoyed it as much as i did.

[dieseljeep]

Originally Posted by rca2000

Don't forget the RCA -based tube with in-lne gun and the "magnetized tape" band over the end of the gun--for convergence. These usually required NO convergence adjustments--that tape did it all, set from the factory. Those tubes were not too bad , either. They hold up a LOT better than the JUNKatron tubes do !! JUNKatrons had an incredible picture...for a short time..before they died and could NOT be brought back. NOT really worth the premium Sony charged for them, often with a shitty, hot chassis to boot.

Sony's picture quality sold the set.
I'm well aware of the CRT's in certain models, that didn't stand up well!
I only replaced CRT's in two Sony sets. One from a junk set and one purchased as a new tube. That was the mid-70's 19" set. That CRT was made in California. I also saw two heavy-beast 26" consoles, where the CRT's were really sick.
I have several Sony's in my possession and all but two have perfect pictures.