Aug 132014
 

I got two Silent Dragon PCBs recently.I never heard about this beat ’em up manufactured by Taito and a quick look at MAME lead me to try a first repair of this cool game.

Board was in quite good shape (a little bit dusty though..)

Silent_Dragon_PCB

When powered it on I got a steady black screen but I could hear all the sounds and also put credits in.So I started to press and flex the board and all the graphics were restored on screen when I touched the area around the TC0180VCU ASIC.So I decided to reflow the ASIC (some pins were really lifted) which ,according to MAME source, controls the video and decode graphics:

TC0180VCU_Taito_ASIC

I was quite sure that I succeeded but I was wrong since the board still played blind.Crearly there was a loose contact somewhere so I started my visual investigation on solderside.There were no broken traces but I came across this:

pin_short

Two pins made contact between them and precisely the VCC pin of a 74LS245 @IC26 and pin 1 (input) of a 74LS04 @IC27.Pin 2 (output) of this 74LS04 was connected to /OE pin of the four GFX MASK ROMs and this explained why there were no graphics at all.After removing the short,I finally could enjoy also with my eyes this game.

Silent_Dragon_fixed

Now time to dump the two PALs on it! 🙂

 Posted by at 10:08 pm

  One Response to “Silent Dragon repair log #1”

  1. Nice work 🙂 I also have the same little desk light that I use to look at pcbs!

    – Ben