Star Tech Journal

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AilgustI991 •
Series /Parallel
Flipper Conversion
Atari Road Riot
Is UL Listed
Charles Bleich
Williams Electronics Games Inc.
Chicago. Illinois
Santa Clara. California
ToPIC
SUBJECT
Conversion of series flipper coils to parallel
flipper coils.
Thank you Atari! Atari's new Road Riot is UL
listed. Seeing that big "UL" sticker on the back of
a cabinet is quite a thrill. This small sticker says
"We Care" from beginning to end.
PROBLEM
The article by Shawn Puckett in the June 1991
STARflECH Journal on Series/Parallel Flipper
Conversion is in error.
REASON
The electrical schematic changes that he has
described are correct but the magnetic fields will
oppose each other between the power and hold-
ing windings. This configuration will work be-
cause the power difference of the holding vs
power windings is very large. This will cause the
coil to be weaker than its true capability during
the power stroke. None of the real benefits for the
design change will be obtained:
Since the Williams series coil has the common
connection of the two winding on lug 2, the
current will flow in opposite directions rather
than in the same direction causing the magnetic
fields of the two windings to oppose each other.
Therefore subtracting energy instead of adding
together.
SOLUTION
Since it is a very difficult task to alter the winding
termination it would be advisable. but not rec-
ommended, that a coil that has been wound for
parallel use be employed.
CONCLUSION
When converting a game, the power delivered by
a coil can and will be different depending on the
coil selected for the replacement. If a coil that is
more powerful than the original one is installed.
damage to other parts on the playfield will occur.
It is always recommended that an exact replace-
ment part be used.
Bill Eaton
NDI
Trying to "after market" a listing is almost impos-
sible. The requirements for that little sticker can
be found on 33 very complex pages of UL22
(Underwriters Labs Reg). Other labs have pro-
vided similar standards based on this one.
SAFETY & QUALITY
Underwriters Laboratories maintain some of the
toughest listing standards in the world. Many
other testing labs use UL standards to design
their own. This seal not only guarantees a safe
design but is often times a seal of quality.
In order to obtain a listing, only approved com-
ponents can be used. Inferior components are
automatically weeded out since most items of
inferior quality won't pass the rigorous testing
required for approval.
Approved components can be identified by a logo
that looks like a combination of the letters U and
R. but it is actually the logo for ANSI. By pur-
chasing approved products and replacement
components and maintaining the integrity of the
equipment (especially three prong plugs and
outlets) you will reap immediate benefits: like
greatly reduced service costs. less down time
and more sleep at night. This last benefit you'll
need to carry the heavy money bags to the bank.
I never look gift horses in the mouth. but I am
encouraged by this example. You should have
little trouble identifying reputable manufac-
tures in the near future. since they will soon
follow suit.