Overhauling the Sega Astro City – Part 3, monitor replacement

Continuing on from part 2 of this series, let’s move on to part 3, which is probably the most expensive one – replacing the monitor in my Sega Astro City.

The problem I’ve had for a while now has been with some persistent issues regarding convergence and clean lines on the existing monitor, but the main issue I’ve had is knocking out some nasty interference on the tube from what looks like some omnipresent unshielded speakers. Despite attacking it with a degaussing wand, I haven’t been able to permanently shift it, and talking to a few ops and techs, I’ve been told the tube’s probably on the way out. Given the machine’s originally from Japan (though the tube’s been changed since it made it’s way to local shores I’d hazard at a guess, given the dodgy chassis driving the tube before I switched to a genuine Pentranic dual-resolution chassis) and has made it’s way across the country, this isn’t surprising.

So, what to do? I floated the idea of grabbing a big 29″ tri-res tube and use that, but the issue with going this way are that 15k games (which are the majority of arcade games out there) generally look a bit rubbish on most tri-res chassis’ compared to a 15k or 15k/24k chassis, and the cost of the tube (well, tube + postage) is enormous. So, what to do?

After asking around at Aussie Arcade, I found out that Jomac can do a 29″ universal chassis that can be used on old TV tubes. So, given a 68cm TV will suit a 29″ tube frame, the prospects get much better. Given the relatively negligible cost of CRTs at the moment (a lot of my fellow arcade fanboys at AA are pros at nabbing working tubes off the side of the road during hard rubbish!), I managed to nab one for pretty much nothing that’s in great physical condition and a prime candidate for plonking into my cab. All I need now is a uni chassis to suit (I’ve already checked in with Jomac and he’ll be able to sort me out), and I’ll be fine to go. Given I’ve already had plenty of practice hooking up chassis components to tubes when my old generic chassis died last year (including safely discharging the tube), the job shouldn’t be too tricky.

So, this means I’ll be able to swap out the old tube for a relatively new one, pair it with a nice 15/24k universal chassis, and be up and running with a great little setup. Definitely makes for an easier and more cost-effective way of swapping tubes around, and will leave me with a working 15/25k Pentranic CH-288 chassis I can either hold on to, or sell off to offset the cost of the new chassis.

So that’s part 3 – part 4 will deal with more scope creep, this time involving the addition of some old PC parts.

To keep track of the whole project, just use the Sega Astro City Overhaul tag – the whole series will be added to it over time.