Turbo - Sega 1981

Picked this one up on 5/29/2012 in Highlands Ranch, CO. Sticker shows serial #16702. Plays blind, so needs a monitor rebuild. Monitor looks like it's been worked on very extensively with many jumpers and the horizontal width coil soldered to the solder side of the deflection board. Sega Nanao 20inch monitor (MC2000 / KB240331B). Coin counter is at 109,319.

Some helpful Turbo related links:

Control Panel Tips: http://forum.arcadecontrols.com/index.php?topic=13701.0

The Turbo Project: http://www.basementarcade.com/arcade/turbo/index.html

KLOV Turbo Listing: http://www.arcade-museum.com/game_detail.php?game_id=10216

Turbo Game Review: http://www.youtube.com/watch?feature=player_embedded&v=qi1UDqSLqfw

Repair Plan:

Recap monitor 6/2/2012 DONE

Replace filter cap on monitor 180V 680uf 6/2/2012 DONE

Fix solder on horizontal coil 6/2/2012 DONE

Go over entire monitor deflection board, fix/replace any burned traces / components 6/2/2012 DONE

6/2/2012 Monitor fixed, TURBO LIVES!!

Repair Log:

6/2/12 Player car started showing up as a white vertical line about 2 inches wide. Collision detection not working (constant crash).

6/3/12 Replaced the light bulbs (4) in the LED score panel with #161 14V.

6/4/12 Replaced the main fuse block and installed new fuses.

6/8/12 Replaced the electolytic and tantalum caps on the power supply board.

6/9/12 Replaced electrolytics on the PROM PCB.

6/9/12 Reseated the eproms on the PROM PCB.

6/9/12 Game works once again!

3/1/13 Game has been having graphics glitches occasionally, sometimes it happens after running for 15-20 min, sometimes it'll run several hours before having trouble.

11/17/13 Replaced Molex game board connectors, the old ones were very loose and worn out. Been running 100% stable with new connectors.

6/16/12 I wanted to add freeplay to Turbo, so I contacted Matt Osborn to get the freeplay ROM file. Here are the instructions and a link to a site that explains how to convert Turbo to non-encrypted roms and a regular Z80 which allows it to use the freeplay rom:

TURBO - Decryption with Epoxy Can Z80

-------------------------------------

Remove the big metal can that's plugged into the socket at position IC 91.

Program the three images into 2764s, and place at the following locations.

EPR01513.bin - Checksum 0E35B3 - IC 76

EPR01514.bin - Checksum 0D0391 - IC 89

EPR01515.bin - Checksum 09Ac9F - IC 103

Fit a regular Z80A in position IC 91.

If the gameplay is intermittant, you may need to replace the socket under IC 91, the pins on the large metal can can damage the socket itself.

http://www.retroclinic.com/leopardcats/decrypt/decryption.htm

6/16/12 Installed the Turbo unencrypted roms, standard Z80 cpu, freeplay chip. Works great and Freeplay!

4/7/14 Game kept having sporadic graphic glitches (notorious on Turbo). I bought a new boardset off KLOV and installed it. Game now works perfectly! New boardset has unencrypted roms. Original boardset suspect bad sockets.

Just got it home 5/29/2012. Overall in good shape. Everything seems to work except the monitor.

Original factory seal:

Horizontal width coil soldered to the back of the deflection PCB. This component seems loose and arc'd and caught fire when I wiggled it. Lesson learned: Don't wiggle it.

Here's the original fuse block:

And here's the new main fuse block with new fuses:

Capped the power supply board (electrolytics and tantalums):

Bottom of cabinet:

Burned new unencrypted roms and freeplay rom + new Z80 cpu.

Here are the old cpu and eproms prior to the conversion to unencrypted:

Here is where the new ROMs and CPU were installed:

New freeplay screen w/attract mode:

Here are the old roms and tin-can CPU:

11/17/2013 Replaced most of the Molex connectors that attach to the game board. Some were very loose and worn out causing a bad connection.

New boardset installed 4/7/14: