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Losmandy G-11 motor cables

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#1 Todd

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Posted 18 March 2009 - 07:38 PM

I have to replace the motor cables on my G-11 which takes RJ-11 six-pin cord. I assumed that six-pin telephone cord would work.

I bought a piece of six-pin phone cord today but it doesn't work.

Perhaps it was the wrong gauge? It doesn't say the gauge on the cord --- I just assumed since it was six-pin and that it looks like RJ-11 that it actually is what I suspect it to be.

Anyone ever replaced their G-11 motor cords?

Thanks!

#2 Todd

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Posted 18 March 2009 - 07:53 PM

Ever have one of those moments where you realize you're not that smart?

I have a friend who works for Bell Canada --- and never thought about him until I made the initial post. I just phoned him. He's going to come over tomorrow and take a look at it.

Little did I know that RJ-11 is just the end plastic piece that clicks in. (DUH!).

He suspects that it's not the correct gauge that I bought.

#3 Strgazr27

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Posted 18 March 2009 - 08:04 PM

Todd,

See this thread Here

#4 Todd

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Posted 18 March 2009 - 08:13 PM

Thanks. I guess I meant RJ12, not RJ11 connectors.

Still, that thread didn't mention the wire gauge. The wire I bought today is six-wire. Strange that it won't work....

Not as strange as having Bell Canada come to service a telescope mount though. ;)

#5 mclewis1

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Posted 19 March 2009 - 12:13 AM

Carefully check the pinouts on the cable at each end and compare them to the original. What you are looking for is whether the original cable is a straight through or crossover cable. A crossover cable is one where pin 1 at one end becomes pin 6 at the other.

I don't know the G-11 cables but I'll guess that they are wired straight through (pin 1 to pin 1). If that is the case your problem is because you are using telephone extension cables which are crossover cables.

Don't worry about wire gauge, since the cables are using modular (RJ11/12) connectors you don't have a choice.

#6 Todd

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Posted 19 March 2009 - 12:20 AM

I can't say....not being a cable expert, pin 1 to pin 1 or crossover doesn't really mean a lot to me. ;)

Saying it's telephone cable does though! ;)

#7 mclewis1

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Posted 19 March 2009 - 12:03 PM

If you pick up the cable and place both ends side by side with both having the tab side down and now compare the colored wires (a magnifying glass often helps). If it's a straight through cable all the colors will be in the same order, if they are reversed then it's a crossover.

#8 rsbfoto

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Posted 19 March 2009 - 01:02 PM

I have to replace the motor cables on my G-11 which takes RJ-11 six-pin cord. I assumed that six-pin telephone cord would work.

I bought a piece of six-pin phone cord today but it doesn't work.

Perhaps it was the wrong gauge? It doesn't say the gauge on the cord --- I just assumed since it was six-pin and that it looks like RJ-11 that it actually is what I suspect it to be.

Anyone ever replaced their G-11 motor cords?

Thanks!


Hi,

You need for the motor 8 lead cables and not 6. If you take a correct look you will see eight contacts inside the big telephone plug.

Look at the Gemini manual on page 130 and it is an RJ-45 connector.

Telephone cable gauge is enough just get 8 wires and not 6.

Pins 1 to 4 are signals from encoder and the pions 5to 8 deliver power to the motor. As you are using 2 leads for each pole of the motor the telephone flat wire gauge is enough.

#9 mclewis1

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Posted 19 March 2009 - 01:10 PM

So Todd, since you don't have much "cable knowledge" how about contacting Losmandy or your dealer for replacement cables instead of trying to do it yourself? That way you'll be safe and there won't be anymore miss information.

... and thanks for the info Ranier.

#10 Kaizu

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Posted 19 March 2009 - 01:40 PM

I just compared three phone cables to Losmandy motor cable. The connectors were similar but...
The first phone cable, only two wires were connected, direct connection.
The second, two wires were connected, crossover connection.
The third, four wires were connected, crossover connection.
The Losmandy cable, all six were connected, direct connection.
I recommend to call some Losmandy dealer and by the original cable. Maybe the smoke also stay inside the controll box.

Kaizu

#11 Todd

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Posted 19 March 2009 - 03:32 PM

Because it can't be that hard of thing to fix. I'm the first to admit that when it comes to electrical stuff I'm certainly not that adept but it's just a simple cable! Plus I'm cheap. ;)

Maybe someone else will learn from this too.

However, in the daylight I do see what you mean (as you stated in a previous post) about the crossover. The phone cable does that while the Losmandy cable does not.

So if I cut off the cable and attach a new connector with the cord turned over (or wait until my Bell Canada friend comes over after work to verify), that should solve the problem.

If the motors were going to burn out they would have done so by now. ;)

But if this doesn't fix it....then I'll order some new cables from Losmandy.

So Todd, since you don't have much "cable knowledge" how about contacting Losmandy or your dealer for replacement cables instead of trying to do it yourself? That way you'll be safe and there won't be anymore miss information.

... and thanks for the info Ranier.








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