September 2016 – JAMMArcade.net

Out Zone repair log #5

PCB Repair Logs Comments Off

Sep 292016

Another Out Zone on the bench and with this one we have five repair logs of this PCB.

Board came in not so great condition, quite dirty :

100_8856

Like all the Out Zone I have troubleshooted, also this PCB suffered from sprites issue, they were garbled and misplaced :

Having a good knowledge of this hardware, I went to probe the involved circuit.All was fine until my logic comparator reported issue on a couple of outputs of a 74ALS163 @17B:

100_8858

The scope confirmed the outputs were floating compared to inputs:

74als163_inputs_outpus_comparing

I removed the IC and the out-of-circuit testing failed miserably:

74als16317b_failed

Another Out Zone saved.See you at the next repair of this great game by Toaplan!

P.O.W. – Prisoners of War repair log

PCB Repair Logs Comments Off

Sep 292016

Got this P.O.W. – Prisoners of War PCB since a long time, bought in a lot of faulty boards from USA :

100_8798

Board was marked by a piece of tape with the words “SPRITE ERROR”.When I first powered the board up, picture could not sync properly on the Philips CM883-II monitor of my supergun (but it did on my Astro City):

I found a workaround by replacing the 100 Ohm resistor connected in series with the SYNC pin of edge connector with a 10 Ohm one.So the sprite error materialized :

As usual I did my visual inspection and found a severed trace on the solderside (involved in the sprites RAM data bus).Patching it cleared the error so game finally booted showing this issue :

100_8729

I noticed that if I shorted some address/data lines of a row of eight 2018 RAMs, further lines were displayed so this was the part of circuit involved.

100_8733_

I went to probe each RAM with my scope and found some irregular activity on data lines of the chip @9K, here is a comparison with a good signal (on the left of the below picture)

data_line_compare

Time to desolder the chip:

100_8946

The out-of-circuit test failed :

20189k_failed

A good RAM chip fixed completely the game.

Raimais PAL dumps added

PAL Updates Comments Off

Sep 272016

I dumped the two PALs from a original Raimais PCB , an obscure maze chase game released by Taito in 1988.Dumps have been successfully tested onto GAL16V8 devices.Board has been kindky provided by ‘robotype’, thanks to him.

Super Hang On sitdown (317-0039) decrypted

Decrypted Updates Comments Off

Sep 192016

A new version of Super Hang On has been added to the decrypted list ! It’s the sitdown version (317-0039), freshly dumped and not yet available in Mame.

Many thanks to Shou for providing the dump and testing the decrypted version !

Hot Shots Tennis PAL dump tested

PAL Updates Comments Off

Sep 192016

I successfully converted from PAL to GAL and tested the Hot Shots Tennis dump we had from an unknown source.My test took place on a bootleg board which has identical layout of original.Equation of bootleg PLD match the ones of original so we mark this dump as working in both boards.

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