New Motherboard Improves Old CRT Television

While browsing AliExpress from his digital basement, [Adrian Black] stumbled upon what seemed like a brand-new mainboard for a CRT television set. He decided to take a gamble and ordered one. It finally arrived, and was indeed a brand new product from 2023.

DIGITAL MAIN BOARD OF TV, Work ath [sic] HONGXUN products with the care and precision of a sculptor in each step, wonderful have no limits

CRT Mainboard Transplant in Progress

Dubious marketing descriptions like “High Definition Digital Color TV Driver Board” aside, this turned out to be a fairly well-designed analog TV board. [Adrian] pulls a 20-year-old Magnavox ( Philips ) color television set from storage and begins the transplant operation. One interesting observation is the Magnavox board has almost the same layout as the new board, except for the orientation of the sections. The new CRT neck board had a different connector than the Magnavox set, but was designed to accept multiple sized sockets. [Adrian] just removed the new socket and replaced it with one from the old set. The mechanical issues were a bit more complicated, but nothing that a Dremel tool and a bit of hot glue can’t fix. The 220 VAC power supply was eventually modified to accept 110 VAC, which also enabled him to reconnect the degaussing coil.

[Adrian] has collected some relevant documentation in this GitHub repository, including schematics. Why bother with this at all? Well, until now, he didn’t have any way to test / view PAL RF signals in his lab. He was gambling on the new mainboard having a PAL tuner. It does, but as an unadvertised bonus, it supports NTSC and SECAM as well — but still not “HD digital color TV”, as far as we know. If you want a multi-standard TV in your lab, this solution may be worth considering. It appears there is still a market somewhere for new CRT televisions. If you have any background on this, please let us know down below in the comments.

36 thoughts on “New Motherboard Improves Old CRT Television

  1. These exist due to the hobby arcade market. Enthusiasts/collectors want original CRT displays and sometimes you’ve got a perfectly good tube with a burned out main board that can be brought back to life with one of these.

  2. What if you have a set with a tube that requires a different HV? Do all modern tubes use 20KV, or is the board somehow detecting the voltage, or do you need a different board for a (hypothetical) bigger tube that requires 25KV?

    Anyone know?

    1. Hi…this Chinese made CRT Utility board will obviously drive up to a screen size of 21″ . I can’t speak from practical experience, but it would still work on a larger tube i.e. the very common old standard 23″ except that it won’t scan to the full screen size.. not really a problem. The neck diameter of many CRT’s around the 21/23 ” size most likely would be close if not identical…I never bothered to check!

  3. Given this “new-new stock” find of a TV analog board, one might wonder if there is still some manufacturer of CRT TVs lurking somewhere in East Asia, or is this just for repair, on the premise that there still enough broken CRT TVs floating around the developing world? Or perhaps there are still enough video gamers who thrive on low-latency? Meanwhile my old Sony CRT sits in the basement revered but unvisited, probably with slowly failing electrolytics and an Apple //c monitor in my attic suffering the same fate.

          1. I had a 4 player PONG table in the 80’s I had picked up from some sale. It was a black and white TV type display. They just chopped the plastic up and stuck it in there.

    1. Actually, if you watch the video, at 9 minutes 33, it does look like they are indeed making new TV in 2023, with (a priori from external appearances as per the pictures) what looks like a very similar (if not the same) board.

    2. Here in Vietnam, there are quite a few broken CRT TVs sitting around. However, they don’t generally get repaired — in the local industrial markets I’ve seen people painstakingly unwinding the copper wires.

      This is done for motors and speakers too. Depending on wire gauge/condition, they are either recycled as copper or sent to another vendor in the market that will re-wind the wire onto motor armatures or speaker coils for resale. These refurbished parts are of dubious efficiency but basically work well enough for horrifying your neighbors with your singing, etc.

  4. Actually if you look closely at the photo it’s got a tuner so must be a domestic television receiver PCB rather than a monitor board for CRT arcade consoles. It also has phono sockets rather than a Scart socket so can’t be destined for the European market. Interesting stuff!!

    1. That reminds me of the 70s.
      Back then, some German TVs (and/or video monitors) had DIN connectors (diode plugs) for AV and RGB.

      The connectors looked similar to what the C64 had used for AV, if memory serves.

      This was so much better than SCART.
      Don’t get me wrong, I’m grateful to be European.

      But SCART was a mess. It was awkward French engineering at its best.
      The connector was flimsy, not mechanical stable.

      It had no provisions for luma/chroma (S-Video), no true i/o for RGB (just an output). The pinout was confusing, leading easily to shorts.

      On the bright side, the 5v input pin for remotely switching to RGB mode was nice. If you lost your remote control, you could at least trigger RGV video mode and use the TV as a monitor.

      Still, DIN or a DB-25 computer plug would have been nice than SCART.
      Or an old school Centronics connector with clamps on the left and right.
      It would have had allowed for even more pins, so each pin had its corresponding ground pin.

  5. I had heard that in some markets, their was a cottage industry converting old CRT computer monitors into TV sets. (the monitors being sent as e-waste to third world places.)

    the video shows that board having Many languages used in Asia and Africa. and working with most analoge broadcast systems. It might even work with Some digital systems. I know when I got my first flat digital TV it was happy to pick up NTSC.

  6. I have a large collection of antique TVs, tho a number of them are non-functional or semi-functional. I’d love to get them fixed up with new electronics but I wouldn’t know enough to do it safely. I’ve worked with mains voltage before building amplifiers and was comfortable with that, but CRTs are a bit of a mystery to me.

    Where do these engineers learn how do this safely in the modern world?

    1. These new engineers heed the warnings from others and have common sense to steer clear from the CRT high voltage and don’t stick hands or tools in while it’s on.

      I always tell people to learn more about repairing CRTs before attempting to repair. I’ve seen Adrian Black do some dumb things on his repairs and seen the comments blow up.

      Check out Arcade Jason, Mike’s Amateur Arcade Monitor Repair and bandersentv on youtube. The first two covers arcade monitors but they work very similar to a TV. bandersentv covers a lot of antique TVs from the 40’s and 50’s.

  7. Working on old TV sets, we always were careful working around the flyback. Once discharged, it was much safer to work on the circuitry. A long screwdriver was a mandatory tool to have!

  8. Thanks for the replies and memories; used to work at: The Brick, a Canadian TV and appliance outlet from Western Canada. Many Tv’s are world products; board gets populated for the country it’s headed for, power supply too. Ali-express for the win.

  9. Somewhere in the world you know there is some dude with a windows 3.1 Machine and NT on another partition with 85 CRT monitors reading this post laughing his ass off and just because it’s funny won’t sell so much as a power cord spare he has. LOL I would say to him I’ll see you 3.1 and raise you a DOS6.2 LMFAO LOL

  10. I’m an arcade operator & have learned alongside others that these work 90% as well as the originals but with a high failure rate. There are tons of working TVs around you, check FB marketplace or Craigslist. Working or non-working arcade chassis can be acquired from FB groups or discord servers. We are keeping them alive for the purists from the fighter scene & the arcade resto scene. The old timers are so gold right now.

  11. The retro market is today huge. Already growing before covid pushed it back into mainstream. And those monitors are in want now.
    Add the revival (finally) in love tape format video…

  12. Last attempt. Does anyone KNOW for sure whether this board can run on North American 110VAC @ 60Hz without Adrian’s modification? Was using an isolation transformer? Was he using a step down transformer? After he did his capacitor modification he says the TV can run on 110 but he never mentions whether it’s running at 50 or 60 Hz. I asked this question on both of his videos about this board but no one has ever replied. I ordered one and I’m waiting for it to arrive from China. I also ordered both a 220 to 110 stepdown transformer and a seperate isolation transformer from Amazon. I hope to be able to return those because I hope I won’t need them! I really think Adrian should have addressed these issues, IMHO. Thanks to anyone who does provide me with an answer!!!

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.