Sega (Toshiba) arcade game 50" projection monitor tube replacement and alignment

If you want to keep your games original, don't hack in an LCD panel. Replace your tubes!

Keep the original 4:3 aspect ratio and have a brilliant picture... Brand new tubes are basically not available, but there is an easier solution: find any old Toshiba RPTV you can junk to pull the tubes out of (In this case, because these are Toshiba sets in the game and the mountings and electrical connections are identical). They can be had for free or very little money on Craigslist. Find one from 1996-2000 with a screen size of 50" to about 63" -- any tubes from that era should work and will drop right in, no matter the number on them.

Replace one tube first to make sure they are compatible. If they are the wrong type (e.g.:tubes meant for dynamic focusing), they simply won't focus well and might arc internally. This will NOT harm anything, just find another set to pull tubes from. These types of incompatible tubes are generally only found in sets 65" and larger, and/or 2001 and newer. So you want smaller & older sets to junk for a tube donor.

You will spend a few hundred on an LCD and a converter board, and it will not look as nice or as bright as "new" tubes.

This video is a walk-through of replacing and setting up a CRT in a Sega/Toshiba P503SGA or P503SGC 50" tri-res rear-projection monitor, including some basic info on convergence and green geometry alignment.

Most 50" Sega games newer than 1998 used this monitor. P503SGF used in Naomi games is the same monitor (identical electronics) with a HD15 (VGA) input instead of 4-BNC. They are both tri-res. Namco's P502GN is probably similar as well, but standard-res only (15.7kHz).