School me on fiber optic system link cables (Sega Super GT)

AUSyTyIN

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School me on fiber optic system link cables (Sega Super GT)

Kind of a confusing read, so hopefully I explain it well enough:

I bought a Sega Super GT that had intermittent connectivity issues between the pair. It would work most of the time, but occasionally reset to the "network checking" screen (which happens when the signal is interrupted). I noticed some damage on the fiber optic cables, so I figure that is the problem. Here is where the problem gets weird.

For reference, each seat has two cables (one send and one receive). In the coin box, there are male to male connectors that connects the cables from one machine to another, as seen here:

*note, the connectors are completely hallow, and do nothing besides alight the ends of the two cables.
IMAG1088.jpg




To repair the problem, I was trying to use a pair of Monster Cables "Interlink LightSpeed 100" fiber optic cables, one of which was still in the packaging, the other being stored in a box of cables for the last ~8 years or so. From here on out, I will refer to the cables by the following:

Old1: 2m original cable with visible crushed and crimp damage
Old2: 5' original cable with minor visible crushed and crimp damage
Old3: 5' original cable with no visible damage
Old4: 5' original cable with no visible damage
New1: slightly used 2m cable stored in a box for years (Monster)
New2: NOS 2m cable removed from it's packaging for this fix (Monster)

As stated before, the machine works with Old1-4 most of the time. If I bypass the couplers seen in the pic, and use Old3 & 4 (the best of the originals) then I get no connectivity. If I connect New1 & 2 in the same manner, I get no connectivity. I experimented around and can get connectivity mixing Old and New cables, but only if I use the couplers (2 cables per run)


First question, assuming the end fittings are the same, are there any differences between fiber optic cables (are there different types)?

Is length an issue?

Is there any reason why two more or less brand new cables hooked directly from one machine to another shouldn't work (yes, I've tried switching ports to make sure I don't have it hooked up backwards)?

Any other thoughts, or is this too confusing to follow?

I have no problem buying 4 brand new cables if that will fix the problem, but at this point I'm not sure it would.
 
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There are different types of optical cables - single mode and multimode. There are also different sizes of the optical fiber itself.

If you don't have the correct cable then you will have communications issues

If the old cables have been crimped, bent at a severe angle, etc... then the fiber in the middle may be broken. You can check this by putting one end of the fiber towards a visible light source (NEVER use the optical transmitter!) and looking at the other. If the light is crisp and bright the cable should be fine. If it's dull, dim, not filling the whole fiber then it is damaged and needs replacing.

Now with that said, if you want to find out what kind of cable you need you'll need to look up the datasheet on the transmitting module on the board. Sega will probably not tell you what you need. ;)

Length can be an issue at times... this is generally cause by too much signal at the receiving end and adding cable helps reduce that signal.

Also, make sure you are connecting the transmit connector to the receive connector on the other board. ;)

RJ
 
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When I bought my "sega touring car championships machines", I was having trouble getting them to link, so I called Ken at irepairsega.com. he advised me to go to radio shack and get a new cable and substitute it for each cable, on at a time until I determine which one is the issue.
What I did instead, was eliminate the interconnect at the coin box, since some of the cables were so long, i just rann the cables straight from one game to the other. I'm not even sure why the have the extra connection at the coin box. Probably just so people don't have to open the games up during set up.
Jayme.
 
The old cables are worse for wear, so I just might swap in two new ones. Is there a good place to buy them online, or should I look local?

When I bought my "sega touring car championships machines", I was having trouble getting them to link, so I called Ken at irepairsega.com. he advised me to go to radio shack and get a new cable and substitute it for each cable, on at a time until I determine which one is the issue.
What I did instead, was eliminate the interconnect at the coin box, since some of the cables were so long, i just rann the cables straight from one game to the other. I'm not even sure why the have the extra connection at the coin box. Probably just so people don't have to open the games up during set up.
Jayme.

That's exactly how I was trying to run it. What type of cable did you get?
 
The optical (toslink) cables sega uses are just cheapo plastic, so they're typically pretty tough -- I've had cables pinched between the coin box & cabinet many times and they usually work fine. I've had plenty of bad ones as well, and the physical damage is always noticeable. If it isn't immediately obvious which cable is bad I usually just shine a light through them and whichever one is dimmer will be the culprit.

Any generic toslink cable can be used to replace them, or you can just run the good ones through to the other side if you don't plan on splitting the twins anytime soon.

you can get 6' toslink here for $1.94 ..10 or 12ft would be better if you need cables to link cabs together. I think Sega typically uses 3 or 4m cables.

Don't be worried about looking into the cables when they're on, they're just GaAs LEDs, not lasers.

edit: I can see the black-ended cable on the left has damage suggesting it was pinched between the coin box & cab. Common problem. Just replace any damaged cable.
 
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The optical (toslink) cables sega uses are just cheapo plastic, so they're typically pretty tough -- I've had cables pinched between the coin box & cabinet many times and they usually work fine. I've had plenty of bad ones as well, and the physical damage is always noticeable. If it isn't immediately obvious which cable is bad I usually just shine a light through them and whichever one is dimmer will be the culprit.

Any generic toslink cable can be used to replace them, or you can just run the good ones through to the other side if you don't plan on splitting the twins anytime soon.

you can get 6' toslink here for $1.94 ..10 or 12ft would be better if you need cables to link cabs together. I think Sega typically uses 3 or 4m cables.

Don't be worried about looking into the cables when they're on, they're just GaAs LEDs, not lasers.

edit: I can see the black-ended cable on the left has damage suggesting it was pinched between the coin box & cab. Common problem. Just replace any damaged cable.

Thanks for the link, I just bought 2. There is a shop across town that has them, but they want $15 per, so I'm buing these for less than my gas money to get over there!

FWIW, the Monster Cables are 2m (6'6") and they reach from one to the other with a bit of room to spare, so I'm hoping the 6' ones will be perfect. If not, I'll just order another set with some new adapters.
 
Don't be worried about looking into the cables when they're on, they're just GaAs LEDs, not lasers.

I err on the side of safety as I was trained on SONET rings and OC192 gear. Those will screw up your vision badly.
 
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