Tony's Arcade

I replaced the picture tube in the Star Castle a couple of years ago and thought I should post the details here. I had no idea I could purchase a brand new tube for Star Castle until I saw a post on the newsgroups from 1997. For US$108, it seems like a pretty good deal. The old tube worked alright; the vectors were getting a bit on the “soft” side, and the tube took a longer than usual time to warm up. It was time to put some more life back into Star Castle and bring it a step closer to the “ultimate state.”

Side note: Replacing the tube was something I did while I was troubleshooting another problem: dim vectors that I could barely see. Using the Cinematronics Vector Monitor FAQ, I tried a few different things, but the tube and video board appeared to be fine. The “dim vector” problem stemmed from the BRIGHT/INTENSIFY circuit on the main game board. (The “Intensify” [Connector J2 pin 12] and “Bright” [Connector J2 pin 14] outputs on the main board didn’t show activity with a logic probe. These dead outputs led to the dim vectors.) Also, the IC at F2 (a 74LS259) was SUPER hot to touch, which is usually a tell-tale sign of a bad IC. F2 is responsible for a few things, including the control panel and… brightness. I replaced it, but that didn’t solve the problem (even though F2 ran cool after that.) The PROMs (C14, D14, E14, F14) were also hotter than the other ICs, but this is apparently normal. I couldn’t figure out the problem, so I had to send the board to Mark Shostak at Cinelabs. He fixed it — the problem turned out to be the IC at location E6, a 74LS163 binary counter that’s part of the LINE DONE circuitry. The LINE DONE circuitry feeds the INTESIFY and BRIGHT circuits, hence the dim vectors.

Back to the picture tube… here’s the replacement information:

Richardson Electronics
1-800-238-7661 (Personal Sales Phone Number)
http://www.rell.com/
Part Number for Tube: 19VARP4

Even though the website listed that part number as “on order”, the rep I talked to said it was in stock. They sent it UPS Ground and I received it a few days later. (They’re in IL, right outside of Chicago.)

Replacing the tube was very easy. Of course, you must DISCHARGE the tube before removing it! Don’t touch the tube or work on it unless you know how to handle a picture tube! There are 4 bolts the hold the tube in place so you can remove and drop in a replacement tube. All I had to do on the tube was unsecure the yoke from the old tube and move the yoke to the new tube. Before tightening the yoke on the new tube, while the game was on I rotated the yoke a bit to make sure the image on the tube was straight. Then, I removed the color screen overlay from the old tube and placed it on the screen of the new tube. I had to remove the old “black sticky tape” and use 3M double sided tape (the “cushion” kind) to stick the overlay onto the new tube.

With the game on, I moved the magnets (those little levers on the end of the yoke) to center the image under the overlay. After everything was lined up, I adjusted the brightness (R11 on the video board.) Everything was perfect after that! The new tube made a world of a difference. The tube warmed up instantly and the vectors were now crisp, clear, and bright! It definitely made the game look brand new.

This entry was posted on Sunday, February 12th, 2006 at 9:52 pm and is filed under Star Castle (1980). You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.