1954 Color TV ID

[Tom9589]

I thought it was a little odd that a Muntz chassis sported both a power transformer and a 5U4. The caption was tricky in that it said the chassis was used in a Muntz TV, not that Muntz made the chassis.

[David Roper]

A power transformer and 5U4 was not only common but omnipresent for the first several years of Muntz TV production, the exception being early 10" sets that used a 5V4--not as damper (they didn't have one!) but for B+.

[Tom9589]

I do remember working on a couple of Muntz's with the 5U4 (5V4?) sitting on top of the transformer. Those TVs also didn't have fine tuning. I'll bet Muntz was real happy when they got rid of the damper tube although they went back to the design with a damper. They liked the 5V4 because its filament drew 1 amp less current than the 5U4.

[NewVista]

The Chromatron looked Super!

Funny how Sony couldn't make it work like Dr Lawrence could in the early 50s!

Sony also couldn't make their video/audio recorders run without a pinch roller (analog-constant-tension)
like Ampex could. An Ampex customer engineer told me "Sony were very jealous of Ampex".

[etype2]

[QUOTE=NewVista;3168351]The Chromatron looked Super!

"Funny how Sony couldn't make it work like Dr Lawrence could in the early 50s!"

I totally disagree with that comment. The Trinitron is an improved Chromatron. The Trinitron was the most successful television design in the world with a 40 year production run, until the flat panels killed the Trinitron.

After Sony acquired the patents and development rights from Paramount Pictures, Sony filed over 100 patents with their own ideas and inventions that made the Chromatron viable and renamed their invention "Trinitron". There were many other companies that worked on the Chromatron, but Sony was the first to make it work.

Doctor Lawrence through Chromatic Television Labratory, demonstrated both one and three gun Chromatron's. All of the original Chromatron principals are used in the Trinitron:

One gun, tri-color vertical phosphor stripes, high brightness by inventing the aperture grill with unbroken vertical slits allowing a greater percentage of the electron energy to reach the phosphors.

Then Sony took the Chromatron design further and improved on it with superior focusing and depth of field.

Finally, Sony actually markeded PDF Chromatrons in Japan and the U.S.

The storys about the struggles Sony had with the single cathode PDF design are true, but they did not give up and as a result the Trinitron was born, son of Chromatron.

[MRX37]

Originally Posted by etype2

I totally disagree with that comment. The Trinitron is an improved Chromatron. The Trinitron was the heaviest television design in the world with a 40 year production run, and countless customers ending up in hospitals for torn muscles and back injuries.

After Sony acquired the patents and development rights from Paramount Pictures, Sony filed over 100 patents with their own ideas and inventions that made the Chromatron the back breaking beast it became, and renamed their invention "Trinitron".

<snip>

The storys about the struggles customers had getting Trinitron's into and out of their homes are true, but they did not give up and as a result many Trinitrons continue to dominate living rooms all across the US... because people learned their lesson and would rather not go through the trouble of moving it again.

Fixed that for you.

[dtvmcdonald]

The key ingredient of real Chromatron is one gun, one cathode, one grid, and dot sequential, which applies to Apple/Indextron too, AND direction to the
vertical stripes not by fine focus and sensing/feedback but active
direction with high RF electric fields at the screen and, produced by grids.

The not really Chromatron KV-7010U has three cathodes and passive (DC)
focus at the screen end by wires. The Trinitron has a much less transparent
mask and no focus, just shadowing, at the screen.

My Indextron is coming back,
I still am looking for a KV7010U.

[NewVista]

The Trinitron is more a Shadowmask type CRT than a Chromatron

The first Trinitrons were bright, but at the expense of resolution: they were embarrassingly low resolution - even for a 12" screen -- like the low resolution GE Portacolor shadowmask with its low density (proportionally larger) holes to make it brighter.

Here's another thing the Japanese couldn't perfect: The Smartphone!
The Japanese hate losing, and nearly went broke rather than kowtow to RCA.
The SONY cinema projector uses LCOS rather than import US tech DLP chips.

[etype2]

Originally Posted by dtvmcdonald

The key ingredient of real Chromatron is one gun, one cathode, one grid, and dot sequential, which applies to Apple/Indextron too, AND direction to the
vertical stripes not by fine focus and sensing/feedback but active
direction with high RF electric fields at the screen and, produced by grids.

The not really Chromatron KV-7010U has three cathodes and passive (DC)
focus at the screen end by wires. The Trinitron has a much less transparent
mask and no focus, just shadowing, at the screen.

My Indextron is coming back,
I still am looking for a KV7010U.

The common belief is that the Chromatron was ONLY A ONE GUN CRT. The original Lawrence Chromatron was designed to be one or three guns and one or three cathodes. The one gun design received all the attention because of its simplicity and theoretical perfect registration. Prototypes were tested in both configurations. The original Trinitron Aperture grill is less efficient then the wire grid, but never the less much brighter in its day then a shadow mask from the same time period. (1968) The Trinitrons were recognized for produceing bright well focused, high resolution images.

[NewVista]

Originally Posted by etype2

(1968) The Trinitrons were recognized for .. high resolution images.

Hogwash!
Ever seen a multiburst on the 1970s Tektronix 650 monitors? The resolution was abysmal!

Sony only stepped up the resolution much later to match the competition.

[old_tv_nut]

The Trinitron originally and for a long time had a coarse grill that would produce terrible moire patterns with 3.58 MHz color subcarrier dots. The video response was strongly filtered to remove any signal above 3 MHz [edit: or maybe less]. The sets, however, did have a very good luminance transient response with carefully phase equalized, equal, preshoots and overshoots. This produced a "sharp," "clean" picture, but not a high-resolution one. TV stations loved them for at least two reasons: they eliminated any video noise above 3 MHz, and, at the time, they had the brightest pictures of any monitors, which facilitated using them for pictures visible to the camera on a set.

As a side note, Tektronix had a program to develop a monitor that had a very small spot size, fine dot pitch, and luma response out to the limit of broadcast cameras (way beyond the 4.2 MHz broadcast signal limit.) The raster lines were clearly visible, much like a monochrome tube. When they showed it to network engineers, the project was shut down, because the studio people hated it.

[etype2]

I'm just a collector/hobbiest. I was never exposed to professional equipment. I was not thinking professional equipment. I was thinking consumer television and in the 1968 era when the Trinitron was introduced and what I saw with my own eyes. It is unfair to compare a consumer television to a professional monitor. That is where I was coming from.

Most people, when seeing CONSUMER Trinitrons for the first time back then were impressed. I too looked at a 1965/66 GE Potracolor in store showrooms. Now that was low resolution.

I saw a 7 inch and 12 inch Trinitron in the NYC Fifth Avenue showroom in 1968. The image quality blew me away. I was so impressed, that I bought one on the spot in 1968.

Speaking of professional studio monitors, I noticed through the decades that televisions control rooms seem to use Sony monitors a lot. I was never in the trade, I worked in real estate, but I base that from watching television and often times, I would see a studio control room shot filled with Sony monitors. One example, the Today Show.

I think we are straying from the original topic of this thread.

[NewVista]

A pair of these iconic Tek monitors were auctioned off (cheaply) at last ETF!
They were iconic and ironic in so much as all that money for a soft picture!
I wonder who made the tube for the prototype hi-res Tektronix monitor?
I'm guessing their production monitors used selected standard Sony units.

[NewVista]

Originally Posted by etype2

... The image quality blew me away...

The consumer version no doubt had edge enhancement at the limits of its res,
-whereas the Tektronix had flat luminance with extra filtering, as was remarked, to eliminate its 3.58/aperture grille beat.

[dieseljeep]

Originally Posted by Tom9589

I do remember working on a couple of Muntz's with the 5U4 (5V4?) sitting on top of the transformer. Those TVs also didn't have fine tuning. I'll bet Muntz was real happy when they got rid of the damper tube although they went back to the design with a damper. They liked the 5V4 because its filament drew 1 amp less current than the 5U4.

All the Muntz sets, larger than 10" used a 5U4 rectifier.
The Hallicrafters 12" set, shown in a different thread used a 5V4. They built that same set for Sears as a 19" metal roundie. IIRC, that model used a 5U4, but all the smaller models still used a 5V4. The power transformer size was impressive, but seemed strange that they only used a 5V4.