Kenwood: Kenwood D710 extension cable

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Hey I'm looking to find the same cable green light use to make. They say it's not normal category cable. I don't want to waste money on S/STP and not work.

Here is what there's look like. ImageUploadedByTapatalk1434238268.523017.jpg
 

n5ims

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Standard computer RJ-45 works well in most situations. If you have a noisy environment (perhaps due to routing it near a car's control lines), shielded cable should help there.

Also, some of those clip-on ferrite cores (ZCAT1325-0530A-BK TDK | Mouser) - those bumps in the cable with TDK on them - are also important in keeping the signal clean. One goes on each end, just like in the original Kenwood cable. In quantities of 10, they're just over a buck each. 2 for the remote cable, 2 for the microphone extension, so you'll need a few.
 
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Well I ran cat6 right now with the ferrites that came with the radio and have nose on my TX.

I bought the extension made by Kenwood, but the mic extension is to short for my mobile install. This is why I'd like to make a custom run.
 

n5ims

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I use standard shielded cat5 cable and an in-line coupler (Cat 5e In-line Coupler - Shielded : 30-9242) to plug the mic into (I have one of those ferrite cores on each end of the cable as well). The in-line coupler allows me to basically move the mic connection into someplace more convenient (and allows me to remove it to store out-of-site when necessary).
 
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I use standard shielded cat5 cable and an in-line coupler (Cat 5e In-line Coupler - Shielded : 30-9242) to plug the mic into (I have one of those ferrite cores on each end of the cable as well). The in-line coupler allows me to basically move the mic connection into someplace more convenient (and allows me to remove it to store out-of-site when necessary).

Did you use STP cat5e or S/STP Cat5e?
 

n5ims

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Did you use STP cat5e or S/STP Cat5e?

I don't really remember which I used, but it I believe it was just standard shielded Cat5e (or 6) twisted pair cable. Looked like standard twisted pair cable with a foil shield over them. Nothing special. Just the shielded patch cable they had at my local supply store. Most of what they sell is unshielded, but if you ask them they can show you their shielded ones (look similar, but only a small color choice and fewer sizes than the unshielded stuff).
 

AK9R

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As the OP understands, the issue with the Kenwood mic cables is that there is a data signal going through the mic cable between the radio and the microphone. Kenwood recognized the potential for the constant, pulsing clock signal from that data line to appear in the mic audio. So, they found a cable which has a shield around the wire that would be used for mic audio. If you look at the wiring of the mic cable in the Kenwood service manual, this individually-shielded wire is plainly visible.

There is all kinds of anecdotal evidence about a pulsing or ticking noise in the mic audio on recent Kenwood mobiles. Some folks have had problems with the stock mic cable. Some folks have made mic cable extensions from various Cat 5E, Cat 6, or shielded variants of Cat 5E or 6 with good success. Some have had significant problems with this approach. Some folks have found that if they make sure the cable connectors are fully seated, the problem goes away. Some folks have found that if they use contact cleaner (CAIG Laboratories - Home of DeoxIT® and Hand-E-Glove®), the problem goes away.

The bottom line, though, is that the noise is in the cable, so an overall shield on the cable does not really address the problem. You have to shield the mic audio line separately from the other wires in the cable.
 

KC8ESL

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I'm betting they had a several thousand foot run of custom cable made up for them and it isnt available. I do that kind if stuff at work and we're the only company allowed to purchase it.

Once you go over 10,000ft of wire, you can do just about anything you want.
 

cmdrwill

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The problem is the choice of pin and cable paring configuration. The Cat5 or even 6 and the pinout puts the data line and mic lines near each other. Ferrite cores will not help.

W9BU has also noted poor RJ45 connector contact problem.

Make up a cable with a separate shielded mic line, just MICE and MIC in this one. You can use CAT cable for the other few lines. Note, some lines are not used in the Mic jack, and you can leave the pins without wires. This will help reduce the crosstalk that causes the ticking problem in the TX audio.

NOTE: Kenwood numbers the RJ45 connectors backwards from the RJ45 standard.

Quick fix: open the cable near the radio end and disconnect the data clock line, and put a switch in so you can turn on the mic buttons if you use them.
 

kc8ufv

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I've successfully used Cat-5e many times for mic cables. Sure, pre-made cables with the pairs of 1-2, 3-6, 4-5, 7-8 will work, but on many radios, the signals are often not optimally paired. To have them work well, you need to pay attention to the pairs. Each pair is twisted at a different rate to minimize crosstalk. You want to make sure your mic line is paired with the mic ground, and if you have a chatty data line in the cable, it should also be paired with a ground. Looking at the standard Kenwood RJ-45 pinout, I'd wire it WOrange, Orange, WGreen, Green, WBlue, Blue, WBrown, Brown.

I've made replacement mic cables for Icom HM-98/HM-133 microphones before, and they are tricker because of the bulk needing to be stacked..... I'd suggest WOrange, Orange, WGreen, WBlue, Wbrown, Brown, Blue, Green for those.
 

cmdrwill

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kc8ufv is correct. First, Kenwood numbers the pins backwards from the RJ45 standard. The mic and mic E need to be on its own twisted pair, same for the data clock and the ground for the keypad on it's own pair. The keypad and the mic E are different grounds in the radio.

There is two capacitors in the mic that aggravate the problem, as we found.

There has been mention of bad from the factory mic cables also.
 

kc8ufv

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Oh, and supplimental information on my previous post - ideally, every signal would be paired with a ground, but often there aren't enough ground connections, so you need to prioritize. I use Cat5 STP (Shielded Twisted Pair) on repeaters that I maintain, and pair all signals with grounds.
 
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