Muter BMR 95 rejuvenator repair log

 Equipment Repair Logs, Repair Logs  Comments Off on Muter BMR 95 rejuvenator repair log
Oct 032016
 

Had this for a while now and its been fantastic.
20161003_091804

There Is a calculation outlined in the manual around predicting the life expectancy of the tube and ive made a little spreadsheet up to deal with that.
The calculation relies on being able to set the G1 voltage on the pot.
20161003_091809

I noticed when I first got this that when I adjusted the G1 pot it was pretty loose feeling and also the reading bounced around everywhere.
Fast forward a year and I’ve come to use this again. I was completely unable to get accurate steady results from the G1 this time so I went to check the pot and found readings like this
20160911_132516

I tried cleaning it out with contact cleaner but its had its day.
I ordered a new 250k pot from CPC and it came a few days later
20160918_170806

Fitting this gave me solid results from the G1.

One thing I recently noticed about this rejuvenator is it has a switch marked “Soft” and “Strong”. Id not really noticed anything wrong with this before but the BMR 95 doesn’t have this option normally. It is present on the BMR 2005 model though.
Looking at it inside it looks to be a factory mod. The same wiring was used and its all part of the same loom. All solder joints look factory as well. Its either a factory mod or a very well done aftermarket mod. Either way Im pretty sure this give me the functionality of the BMR 2005.

 Posted by at 9:33 am

Out Zone repair log #5

 PCB Repair Logs  Comments Off on Out Zone repair log #5
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:

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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!

 

 Posted by at 11:44 pm

P.O.W. – Prisoners of War repair log

 PCB Repair Logs  Comments Off on P.O.W. – Prisoners of War repair log
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 :

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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.

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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:

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The out-of-circuit test failed :

20189k_failed

A good RAM chip fixed completely the game.

 

 Posted by at 9:34 pm

Raimais PAL dumps added

 PAL Updates  Comments Off on Raimais PAL dumps added
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.

 Posted by at 2:48 pm

Super Hang On sitdown (317-0039) decrypted

 Decrypted Updates  Comments Off on Super Hang On sitdown (317-0039) decrypted
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 !

 Posted by at 8:17 pm