chicago coin demolition derby tech help

[Guest]

Archived from groups: rec.games.video.arcade.collecting (More info?)

I have a friend that has just bought a chicago coin destruction derby.

The game comes up in attract mode (one car graphics seems to be garbled).

The game does not enter game mode when coins are entered or when the start
button is pushed.

I checked the power supply and it is outputting 5.4 volts at the supply.


Any ideas on what I should do next? I have fixed video games before, but
this one is a tad old for what I am normally used to.

--
Mickster

Visit my website and see my arcade!!

http://mickster.freeservers.com

 

[Guest]

Archived from groups: rec.games.video.arcade.collecting (More info?)

On 2005-08-11 14:30:52 -0700, "Mickey Johnson" <mickster@derbyworks.net> said:

> I have a friend that has just bought a chicago coin destruction derby.
>
> The game comes up in attract mode (one car graphics seems to be garbled).
>
> The game does not enter game mode when coins are entered or when the
> start button is pushed.
>
> I checked the power supply and it is outputting 5.4 volts at the supply.
>
>
> Any ideas on what I should do next? I have fixed video games before,
> but this one is a tad old for what I am normally used to.

Older games often needed BOTH circuits of the coin switch wired in for
the game to start. So see if your schematic shows both NC and NO as
used.

John :-#)#
--
(Please post followups or tech enquires to the newsgroup) John's
Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 Call
(604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
www.flippers.com "Old pinballers never die, they
just flip out."

 

[Taxman]

Archived from groups: rec.games.video.arcade.collecting (More info?)

Wow, are you in for a mess. These are a real pain since there are no PROM
chips holding the cars shapes or sounds, it is all analog circuits. So the
first thing you need is a schematic right? Got that? If not let me know, I
have the original docs in mine. I have two problems, car 1 sound (ordered
new pots for that) and my score/time windows show up as white blocks.
(working on that). It can be anything from a bad transistor to a bad lan
pad or cold solder joint (about two million of those right?)

This game is also covered with about 40 1uFd Electrolytic caps. Lucky they
are not high voltage or you would have to replace them all, but still 28
years from a component rated for 10 is pretty good).

Where are you, I am in South West CT. The outside condition is in too good
of shape for me to let it die.

- Dave

"Mickey Johnson" <mickster@derbyworks.net> wrote in message
news:11fngsanfhd6gbb@news.supernews.com...
> I have a friend that has just bought a chicago coin destruction derby.
>
> The game comes up in attract mode (one car graphics seems to be garbled).
>
> The game does not enter game mode when coins are entered or when the start
> button is pushed.
>
> I checked the power supply and it is outputting 5.4 volts at the supply.
>
>
> Any ideas on what I should do next? I have fixed video games before, but
> this one is a tad old for what I am normally used to.
>
> --
> Mickster
>
> Visit my website and see my arcade!!
>
> http://mickster.freeservers.com
>
>

 

[Guest]

Archived from groups: rec.games.video.arcade.collecting (More info?)

I am located 3 hours southwest of chicago (near the mississippi river).

I just downloaded the schematic, so hopefully in the next couple of days I
can look into it.

I have a feeling its probably going to go to alex at electron forge.

--
Mickster

Visit my website and see my arcade!!

http://mickster.freeservers.com

"Taxman" <NOSPAMdavid.tkacs@snet.net> wrote in message
news:43RKe.425$bp5.139@newssvr24.news.prodigy.net...
> Wow, are you in for a mess. These are a real pain since there are no PROM
> chips holding the cars shapes or sounds, it is all analog circuits. So
> the
> first thing you need is a schematic right? Got that? If not let me know,
> I
> have the original docs in mine. I have two problems, car 1 sound (ordered
> new pots for that) and my score/time windows show up as white blocks.
> (working on that). It can be anything from a bad transistor to a bad lan
> pad or cold solder joint (about two million of those right?)
>
> This game is also covered with about 40 1uFd Electrolytic caps. Lucky
> they
> are not high voltage or you would have to replace them all, but still 28
> years from a component rated for 10 is pretty good).
>
> Where are you, I am in South West CT. The outside condition is in too
> good
> of shape for me to let it die.
>
> - Dave
>
> "Mickey Johnson" <mickster@derbyworks.net> wrote in message
> news:11fngsanfhd6gbb@news.supernews.com...
>> I have a friend that has just bought a chicago coin destruction derby.
>>
>> The game comes up in attract mode (one car graphics seems to be garbled).
>>
>> The game does not enter game mode when coins are entered or when the
>> start
>> button is pushed.
>>
>> I checked the power supply and it is outputting 5.4 volts at the supply.
>>
>>
>> Any ideas on what I should do next? I have fixed video games before,
>> but
>> this one is a tad old for what I am normally used to.
>>
>> --
>> Mickster
>>
>> Visit my website and see my arcade!!
>>
>> http://mickster.freeservers.com
>>
>>
>
>

 

[Guest]

Archived from groups: rec.games.video.arcade.collecting (More info?)

> Wow, are you in for a mess. These are a real pain since there are no PROM
> chips holding the cars shapes or sounds, it is all analog circuits.

That's not true - they are essentially the same PROM images as Death Race.
You must be thinking of a different game. Death Race, Demolition Derby and
Destruction Derby are almost identical in design (but are not all plug-compatible).

> It can be anything from a bad transistor to a bad lan
> pad or cold solder joint (about two million of those right?)

Pretty unlikely that it's a cold solder joint on in this case, IMHO. This board doesn't
have 0.156" headers which are subject to large mechanical stresses like
on monitors and some Atari boards. Solder joints that tend to break are usually
associated with large thermal masses that don't get heated up fully during the
wave soldering process and/or are subject to high mechanical stresses from plugging
and unplugging. Of course, YMMV. Based on my experience with these boards,
(which is not infinite by any stretch of the imagination) most of the problems both you
guys are describing are probably semiconductor component failures. The 5.4V you
mentioned is too high if you are measuring it at the actual PCB, but if you are measuring
it at the power supply then it's about right. There is a lot of TTL stuff on those boards and
so there's a pretty hefty voltage drop across the wiring harness.

> > The game does not enter game mode when coins are entered or when the start
> > button is pushed.

John's probably right about the coin switch N.C. requirement. I don't have my notes for
DD handy to double-check.

Alex
----
ayeckley@elektronforge.com
www.elektronforge.com