Topics

An alternate view - (Was Re: Kenwood TM-D700A - Don't use a telephone cable as an extension cable)


Tom Schaefer NY4I
 

I have to add something to this (I hope). First, to clarify, I presume when one says "telephone cable" we are not talking about a simple silver satin cable, but something of at least CAT5 quality (its common to use CAT3 for POTS lines). My experience is standard CAT5 can definitely fail, BUT, I switched to a cable that was both shielded and made for mobile installations. Regular CAT5 cable and connections are not supposed to be moved much (either plugged and unplugged or subject to vibration). Using a shielded cable and a cable made for mobility, I see no issues with regular CAT5e cable and very nice stress relief connectors. I do use them for all the inter-connects from the trunk to the radios and microphones.

I disagree with using one case as a cautionary tale just as I would disagree with using only one case of it working as confirmation bias. I believe if polled, most folks on this list would say they had positive experiences with good CAT5 connections (including CAT5e rated double females jacks to connect the Mic and control head. I cannot stress enough how you have to use strain-relief on the connectors just like a LAN patch panel.

Tom Schaefer, NY4I

PS A note on the horror of silver satin is that you have to make sure it is not crossed-over. I have just as many of those that are crossed over as straight-through, but I picked those up from the trash back in my Harris Digital Telephone Systems days (those are the industry equivalent of Tribbles :) ).



Jim K5JG <k5jg@...>
 

I have recently had the same experience with telephone cable not working. I made three or four cables myself, using the correct crimp tool, and they would not work. Even though the cable is supposed to be wired straight through, I made one with the two data lines reversed on one end. Naturally, that didn't work either. Bottom line, I could never get the radio to turn on with the home brew cables.

Then I found a guy on eBay selling TM-D700A aftermarket extension kits and took a chance on one. Turns out that it, too, is made from telephone cable (apparently a better grade of cable) and it does not work properly. The radio will turn on, but only about 25% of the time.

I don't know what the magic is, however...

Kenwood still sells the cable. The part number listed in the manual is no longer valid, but Kenwood Customer Service gave me the new one. It is E30-3409-05 and can be ordered from PacParts (used to be Pacific Coast Parts) who handles replacement part sales for Kenwood. The downside is that it costs $25.76, and that probably doesn't include shipping.

73, Jim K5JG

Thomas Schaefer wrote:

I have to add something to this (I hope). First, to clarify, I presume when one says "telephone cable" we are not talking about a simple silver satin cable, but something of at least CAT5 quality (its common to use CAT3 for POTS lines). My experience is standard CAT5 can definitely fail, BUT, I switched to a cable that was both shielded and made for mobile installations. Regular CAT5 cable and connections are not supposed to be moved much (either plugged and unplugged or subject to vibration). Using a shielded cable and a cable made for mobility, I see no issues with regular CAT5e cable and very nice stress relief connectors. I do use them for all the inter-connects from the trunk to the radios and microphones.
I disagree with using one case as a cautionary tale just as I would disagree with using only one case of it working as confirmation bias. I believe if polled, most folks on this list would say they had positive experiences with good CAT5 connections (including CAT5e rated double females jacks to connect the Mic and control head. I cannot stress enough how you have to use strain-relief on the connectors just like a LAN patch panel.
Tom Schaefer, NY4I
PS A note on the horror of silver satin is that you have to make sure it is not crossed-over. I have just as many of those that are crossed over as straight-through, but I picked those up from the trash back in my Harris Digital Telephone Systems days (those are the industry equivalent of Tribbles :) ).

------------------------------------
Community email addresses:
Post message: TMD700A@...
Subscribe: TMD700A-subscribe@...
Unsubscribe: TMD700A-unsubscribe@...
List owner: TMD700A-owner@...
Shortcut URL to this page:
http://www.onelist.com/community/TMD700AYahoo! Groups Links


Tom Schaefer NY4I
 

I'm not sure how to answer that except to say that the cables of course need to be wired correctly. I use the CAT5e cables and stress relief connectors I mentioned. I also make sure I use couplers that are rated for CAT5e. The cheap ones that happen to fit an RJ45 are not good for anything other than real telephones. Since I switched to the cable I mentioned earlier and good connections, I have had no issues. I will also say that the only time I did have a failure was when I just terminated the Mic extension cable in a cable I stuck next to the seat. Keep he cable from moving and life is much better.

Platinum Tools makes some nice RJ45s that make it quite easy to make good connections. You slide the wires through the connector so it is easy to sort them in the right order. I threw out all my other plugs for these as my eyes are not as good as they used to be for close-up stuff. http://amzn.com/B001AZLS6Y . I have no interest in the company—just a satisfied customer with more money than time (they do cost more).

Regards,

Tom Schaefer

727-437-2771

On Aug 1, 2013, at 5:23 PM, Jim K5JG <k5jg@...> wrote:

I have recently had the same experience with telephone cable not
working. I made three or four cables myself, using the correct crimp
tool, and they would not work. Even though the cable is supposed to be
wired straight through, I made one with the two data lines reversed on
one end. Naturally, that didn't work either. Bottom line, I could never
get the radio to turn on with the home brew cables.

Then I found a guy on eBay selling TM-D700A aftermarket extension kits
and took a chance on one. Turns out that it, too, is made from telephone
cable (apparently a better grade of cable) and it does not work
properly. The radio will turn on, but only about 25% of the time.

I don't know what the magic is, however...

Kenwood still sells the cable. The part number listed in the manual is
no longer valid, but Kenwood Customer Service gave me the new one. It is
E30-3409-05 and can be ordered from PacParts (used to be Pacific Coast
Parts) who handles replacement part sales for Kenwood. The downside is
that it costs $25.76, and that probably doesn't include shipping.

73, Jim K5JG

Thomas Schaefer wrote:
I have to add something to this (I hope). First, to clarify, I presume when one says "telephone cable" we are not talking about a simple silver satin cable, but something of at least CAT5 quality (its common to use CAT3 for POTS lines). My experience is standard CAT5 can definitely fail, BUT, I switched to a cable that was both shielded and made for mobile installations. Regular CAT5 cable and connections are not supposed to be moved much (either plugged and unplugged or subject to vibration). Using a shielded cable and a cable made for mobility, I see no issues with regular CAT5e cable and very nice stress relief connectors. I do use them for all the inter-connects from the trunk to the radios and microphones.

I disagree with using one case as a cautionary tale just as I would disagree with using only one case of it working as confirmation bias. I believe if polled, most folks on this list would say they had positive experiences with good CAT5 connections (including CAT5e rated double females jacks to connect the Mic and control head. I cannot stress enough how you have to use strain-relief on the connectors just like a LAN patch panel.

Tom Schaefer, NY4I

PS A note on the horror of silver satin is that you have to make sure it is not crossed-over. I have just as many of those that are crossed over as straight-through, but I picked those up from the trash back in my Harris Digital Telephone Systems days (those are the industry equivalent of Tribbles :) ).



------------------------------------

Community email addresses:
Post message: TMD700A@...
Subscribe: TMD700A-subscribe@...
Unsubscribe: TMD700A-unsubscribe@...
List owner: TMD700A-owner@...

Shortcut URL to this page:
http://www.onelist.com/community/TMD700AYahoo! Groups Links




------------------------------------

Community email addresses:
Post message: TMD700A@...
Subscribe: TMD700A-subscribe@...
Unsubscribe: TMD700A-unsubscribe@...
List owner: TMD700A-owner@...

Shortcut URL to this page:
http://www.onelist.com/community/TMD700AYahoo! Groups Links