MAMEWorld Forums - EmuChat - Re: Space Invaders emulation

>Schematics in arcade manuals (assuming what was posted was snipped from and not
>proofread/compared to an actual board?) are not always correct and have been known to not
>be 100% accurate in all instances. It happens much more than anyone would care to admit.
>What this would take is direct examination, translation and proofreading of the sound
>sections of the board to ensure accuracy.

Yep. Numerous past examples. The amusing one iirc was when Juergen B. was trying to do Atari Space Race simulation in spring 2009 and posting results on emuchat forum while referring to using schematics from an Atari Space Race second revision manual and the schematics had many multiple mistakes in that particular manual.

It got to the point where one of the posters on the forum had asked was: "Atari trying to sabotage Space Race cab owners into accidentally destroying their Space Race cabs if using that specific manual to do pcb repairs?"

This is the stuff that Derrick Renaud had predicted back in his post from 2003 of the challenges facing non-cpu emulation at the time. Derrick basically stated don't rely on paperwork alone. If a pcb that is for future emulation is accessible, get it and use it first before relying on schematics.

There is also another factor that folks might overlook. Gyrovision had purchased Sega Congo Bongo pcbs in order to make improved audio recording external sample sound effects that were to be used with MAME. One of the Congo Bongo pcbs wasn't working. Gyrovision had eventually noticed that the non-working Congo Bongo pcb had a previous butchered repair job in which the Congo Bongo pcb had parts that were not compatible with Congo Bongo pcb.

So there might be a rare occasion where it might not be misprints/typos in schematics, but actual previous piss-poor quality pcb repair work done by someone that had no business in pcb repair work. :-)