After 6 Years As Road Ornament A Widescreen Sony Trinitron Lives Again

After previously adopting a big Sony Trinitron CRT TV that had been trying to hitch a ride along the side of a road in Italy for at least six years, [Happychoice] didn’t give up on trying to fix it, with the second part showing the TV being more or less fully fixed up.

In the first part of this mini-series, the TV had been salvaged and had most of the dirt as well as local flora and fauna evicted before an attempt was made to fix it. Unfortunately despite the insides looking remarkably clean and intact considering its use as a road-side ornament, that video ended with the controller refusing to power up due to issues with the power supply.

In this sequel we get to see what six years of weather exposure means in terms of what components to replace in a CRT TV like this. Unsurprisingly this means mostly replacing most of the capacitors, at least on the power supply board, as well as the neck board for the actual CRT. A couple of MOSFETs also tested open, so they were replaced too.

With those fresh new parts the TV fired right up again, and with a Wii console connected it looks pretty spiffy running games like Persona 4. Fortunately modern CRT TVs like these have a built-in service menu that you can access with the remote, so that you can tweak picture alignment and other settings without having to stick a screwdriver into the back of the TV to fiddle with a potentiometer whilst also keeping an eye on the picture.

Although there are undoubtedly more components on the PCBs and of course one grimy speaker to give some TLC, it does show that as long as the tube itself is intact, it’s definitely worth it to give repairing a shot.

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The Stages Of Grief In Repairing A Trinitron Found In The Trash

Sometimes you see a project just staring at you with proverbial puppy dog eyes and you just cannot look away. In the case of a once rather nice Sony TV it was the smooth 32″ Trinitron CRT that gave [Happychoice] that look when he came across it along the side of the road. Naturally he had to beg the owner of the junkyard to please let him adopt the pupp^Wjunked TV and attempted an ill-advised repair.

Some later sleuthing revealed that this poor TV had been sitting on the side of that road for at least six years, exposed to the worst that the Italian weather and local fauna could do to it, so it was no surprise that all he got out of it even after cleaning and some repairs was a sad triple-blink of the power LED. This indicated that something on the control board was very unhappy about the status of the power supply.

Over the course of a few months this project went correspondingly from careful optimism down to the depths of depression, through the fields of bargaining and into the blue skies of acceptance of a likely far more involved repair session than originally assumed. That said, the CRT itself looks to be in pretty good nick, as do the PCBs barring the few sketchy resistors that already got replaced.

We would like to congratulate [Happychoice] on the acquisition of a fun new repair project and wish him all the luck on bringing this beast of a TV back to life.

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A CRT Monitor From An Obsolete Logic Analyzer

The designers of older equipment that contained a CRT monitor rarely made the effort to design their own driver and deflection circuitry. Instead they were more likely to buy an off  the shelf assembly from a monitor manufacturer, and simply supply it with their video. [TomV] has an old HP 16500A logic analyzer, and in it he found a Sony monitor chassis. With a quest for a microfiche service manual and a bit of reverse engineering, he was able to hook it up to a VGA port and use it as an extension monitor for his laptop.

The monitor chassis is a Sony CHM-9001-00, which sports their 10″ Trinitron tube. These were among the very best CRT tubes of the day, making it the type of module 1990s hacker would have been very pleased to get their hands on. Here in 2022 a look at the monitor’s 40-pin connector reveals a standard RGB interface which the service manual confirms is within the voltage range to be driven from a VGA output. A Thinkpad X220 is pressed into service, with a 576 by 360 pixel at 60 Hz video mode defined, and there we have it, a modern desktop on an obsolete piece of test equipment.

The intended destination for this monitor is a small arcade cabinet, so it needed to be independent of the HP chassis. The required 120 VDC supply comes from an inverter designed for solar battery charging, which balked at the inrush current from the monitor when fed with 12 V. Increasing the supply voltage on the low voltage side solved that, leading to a very serviceable monitor. We have no use for one, but we’d be lying if we said we didn’t want one.

Perhaps you may have wondered, what made Trinitrons so good?

Why Sony’s Trinitron Tubes Were The Best

If you’re old enough to remember Cathode Ray Tube (CRT) Televisions, you probably remember that Sony sold the top products. Their Trinitron tubes always made the best TVs and Computer Monitors. [Alec Watson] dives into the history of the Sony Trinitron tube.

Sony Color TVs didn’t start with Trinitron — for several years, Sony sold Chromatron tubes. Chromatron tubes used individually charged wires placed just behind the phosphor screen. The tubes worked, but they were expensive and didn’t offer any advantage over common shadow mask tubes. It was clear the company had to innovate, and thanks to some creative engineering, the Trinitron was born.

Closeup of a Trinitron tube shows unbroken vertical stripes which led to a brighter picture.

All color TV’s shoot three electron guns at a phosphor screen. Typical color TVs use a shadow mask — a metal sheet with tiny holes cut out. The holes ensure that the electron guns hit only the red, green and blue dots of phosphor. Trinitrons use vertical bars of single phosphor color and a picket fence like aperture grille. The aperture grill blocks less of the electron beam than a shadow mask, which results in a much brighter image. Trinitrons also use a single electron gun, with three separate cathodes.

[Alec] is doing some amazing work describing early TV systems and retro consumer electronics over on his YouTube channel, Technology Connections. We’ve added him to our Must watch subscription list.

Interested in retro CRTs? Check out Dan’s article on cleaning up the fogged plastic safety screen on the front of many CRTs.

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