View Full Version : Found a Sony IDX-5000 Indextron


etype2
12-16-2015, 08:24 AM
First impressions. It looks stark, not particularly attractive. The cabinet is constructed of heavy gage metal and durable. It’s built like a vault around a small 5.25 inch CRT. Vastly superior resolution compared to the Sony KVX 370 Watch Cube Indextron shown next, with incredibly bright images. The phosphor and index stripes are much finer and closely spaced together. The image resolution and look of the CRT face is similar to a Sony KV-5300 five inch Trintron but about 5 times brighter and the black level is better. A quick analyis since acquiring the set on November 19, 2015, we set the controls to our personal preference and when the scene shifts to a pure white background, it actually hurt my eyes from the brightness. I was surprised to see a liquid bubble in front of the CRT face when we tilted the cabinet to check it out. The Indextron CRT has a liquid cooling cell attached to the faceplate, I think it’s a ethylene glycol-water mixture. An internal fan can be heard. Amazingly, after two hours of operation, the cabinet is cool to the touch and no heat is detected from the front vents seen in the below photos. The IDX-5000 has a 5.25 inch CRT.

I have been looking for this set for six years. It is extremely rare and we have never seen a photograph, let alone the actual unit. I found the service manual in November, 2010 and after extensive searching, never found anything else until now. The serial number tag on the back of the set is 17, an early production unit. I don’t think many of these sets came off the line. The set is very heavy, weighing over 24 lb, with a durable metal cabinet. The plastic screen cover can be removed for cleaning. When powering up, the audio comes up instantly, followed by the fan, then a bright white screen and 9 seconds later a beautiful, colorful, indexed image appears. The first time I saw it, the brightness overwhelmed me. The imaging is excellent. The factory states the color temperature is set at 6500 kelvin, but I have not verified this. All the rotary controls on the front of the set are push buttons. The user pushes in to adjust and they pop out. After adjustment, the buttons push in to lock. There are two video/audio line in and outs with BNC connectors, an RCA A/V input and a DC out. We read that the CRT produces 4800 nit peak white. I have not been exposed to professional color monitors, but this CRT produces the brightest light I have ever seen. We believe Sony designed this monitor to work well in bright outdoor environments. Having no shadow mask or arpeture grill blocking the electrons from striking the phosphors explains the brightness and amazingly with just one electron beam. We believe the beam is driven harder then the consumer KVX-370 Indextron. This same basic CRT is used in the Sony Vidimagic Indextron FP-62 one tube projector shown above. Information on the IDX-5000 is limited, we don’t know much more. The previous owner sells thousands of professional audio and video products based near Los Angles, California.

I will update with a few photos.

http://www.visions4.net/journal/wp-content/uploads/image59.jpeg

See this link for more photos. Scroll down to 1987. http://www.visions4.net/journal/time-line/page-two/page-two-a/page-three/page-three-a/indextron/

Captainclock
12-29-2015, 08:05 PM
So what's the difference between an Indextron and a Trinitron? I'm wondering because there were also Trinitron video monitors like this as well.

jr_tech
12-29-2015, 10:40 PM
WOW, I am actually speechless! Always thought that there was the basis of a cool monitor lurking inside my Videobeam FP 60 projector.

Congratulations on finding a holy grail!

jr

Electronic M
12-30-2015, 03:12 AM
So what's the difference between an Indextron and a Trinitron? I'm wondering because there were also Trinitron video monitors like this as well.

A world of difference. It boils down to the indextron not using a shadow mask (which means 100% gun emission hits the phosphor = brighter picture), but instead making one color phosphor glow in the just the visible color they made it also glow in (IIRC) the UV spectrum....The UV light was picked up by a photo sensor and used to control which primary color signal was sent to the single gun....It is the culmination of the research the Japanese made into making a practical version of the alternative 50's color CRT designs that the 15GP22 delta-gun CRT put a damper on the design of....

Captainclock
12-30-2015, 11:30 AM
A world of difference. It boils down to the indextron not using a shadow mask (which means 100% gun emission hits the phosphor = brighter picture), but instead making one color phosphor glow in the just the visible color they made it also glow in (IIRC) the UV spectrum....The UV light was picked up by a photo sensor and used to control which primary color signal was sent to the single gun....It is the culmination of the research the Japanese made into making a practical version of the alternative 50's color CRT designs that the 15GP22 delta-gun CRT put a damper on the design of....

Interesting, and what 1950s Color CRT Designs was this tube trying to mimic? Just wondering because I didn't know that we had any designs like this in the 1950s for color picture tubes... :scratch2:

etype2
12-30-2015, 12:07 PM
jr,

If you could find a spare FP 60, might be an interesting project to convert to a monitor. :-)

The beam index CRT (and Chromatron) was created as an alternative, (not to minic) to the three gun shadow mask CRT in the late 1940's and 1950's. They were submitted to the FCC during the color trials for evaluation along with the three gun, shadow mask CRT's. The early 50's shadow mask tubes blocked as much as 85% of the light and were dim by today's standards. Other companies other then RCA had proposals for much brighter CRT's to solve the problem of dim images. Starting in 1949, Philco began work on the beam index tube, code named Apple. After 10 years of work a viable set could not be developed and the project was terminated. One of Philco's engineers tried to resurrect the Apple tube in the 1970's. He called it the Uniray and good working prototypes were produced, but lack of funding and interest killed that project as well.

The difficult signal processing of the beam index tube were solved in the early 1980's. Another benefit, in theory, the beam index tube has perfect purity, because there is only one beam, no convergence is needed and no convergence parts and circuitry is required, simplifying the set.

old_tv_nut
12-30-2015, 12:19 PM
Interesting, and what 1950s Color CRT Designs was this tube trying to mimic? Just wondering because I didn't know that we had any designs like this in the 1950s for color picture tubes... :scratch2:

For example, RCA had a one-gun version of the shadow mask tube. The idea was to modulate the "purity field" so that a single beam could approach the shadow mask to hit either red or green or blue.

Eric H
12-30-2015, 12:39 PM
I believe the Indextron and the Trinitron were based on the Philco "Apple" CRT.

http://www.earlytelevision.org/apple_crt.html

etype2
12-30-2015, 01:07 PM
I believe the Indextron and the Trinitron were based on the Philco "Apple" CRT.

http://www.earlytelevision.org/apple_crt.html

The Trinitron is an improved Chromatron. The Indextron is indeed based on the Philco Apple CRT.

The Chromatron uses a different operating system based on post deflection focusing. Just like a beam index tube, the Chromatron uses a single electron beam, but the difference is that that single beam is accelerated and then focused onto the tri-color phosphor stripes by an electronic lens which modulates and "wiggles" the beam to the correct RGB stripe after passing through a grid of fine wires that are charged with high voltage.

A beam index CRT has no grid of wires, instead uses index stripes which emit ultra violet light. The UV light is collected and detected by photo diodes which then "index" the single electron beam to the correct RGB stripe. The critical part is that the beam spot must be maintained so as not to spill into the adjacent RGB stripe.

Captainclock
12-30-2015, 01:10 PM
Interesting... :scratch2: