Kenwood KMC-9 Cable Replacement?

[kenwoodgeek]

Hey everyone,

It's been a while since I've posted on here. I see the design has changed.

I'm looking for some microphone help. At my work, we have a Kenwood NX-800H base station rig that our dispatchers use on a daily basis. It's a very ghetto rig that our radio maintenance company worked on last year. The radio has one 8-pin cable coming out of it running to a little junction box/telephone splitter thing. That allows two KMC-9 6-pin desktop microphones to be connected to the radio and used at the same time.

The rig was working great up until early this year, when the one microphone decided to start transmitting a buzzing noise when keyed and nothing else. For a while, I was fixing it for them by stretching and playing around with the cable. After a while, that stopped method stopped working as well. So the one dispatcher has just been using a portable on her side of the desk.

I finally unplugged the microphone and have a chance to check it out over these next two weeks. Now that I have it home, I've plugged it in to my radios, and I'm having no issues. Transmits loud and clear audio with my TK-8180. I suspect I "fixed" it again when I wrapped the cable around the mike for transport.

Unless it's an issue with the rig (I will put a probably very unhelpful pic down below), I suspect it needs a whole new cable. Before I tear into the microphone, what do I need to know? Is a cable replacement possible? How hard is it? Will a typical 6-pin telephone cable work, or do I need to order a special one?

Thanks in advance!

https://flic.kr/p/2cCuird

 

[mmckenna]

You can have a Kenwood dealer order a new cable for the mic:

KMC-9 (6 pin RJ-12) E30-2080-08
KMC-9B (12 pin round) E30-3358-05
KMC-9C (8 pin RJ-45) E30-3367-08

However, it's very likely the cable got yanked on. If it was me, I'd disassemble the mic and make sure the cable is still plugged into the circuit board all the way. If that doesn't fix it, then replace the RJ-45 on the end.

The NX-x00 and TK-x180 radios use the KMC-9C with the RJ-45, HOWEVER, the KMC-9 with the RJ-12 will work just fine, same pinout.

 

[domes]

8-pin CAT5 cable can be substituted for mic cord. It is too stiff to use on hand mics that get handled but works fine for base mics. You can save yourself a lot of trouble though if you buy the CAT5 version of those junction boxes. It has a RJ- number but I can't remember it off hand. There is also an end-to-end union and a "T" but the mic jack on the radio is inset too far and the edge of the radio prevents the T from securely snapping in. These are computer hardware not telephone hardware. We always seem to have a customer that needs a couple extra feet of mic cord so I give them a union we pay a couple bucks for plus a 6ft CAT5 and it works fine, even with Nexedge digital. The competition would charge $150 labor plus another $200 for DMR approved audio accessories to keep the RF data burst from affecting DMR audio.

You may or may not know this but when using more than one mic on the same radio you should open each mic and check the internal mic contacts. Some mics do not switch the mic element thru PTT contacts and some have switch contacts for the element but the contacts are jumped from the factory. You should make sure that both of your mics are not picking up audio when you PTT.

 

[westcoaster]

It has a RJ- number but I can't remember it off hand.

RJ-45 is the 8 pin jack.

It looks like they used an "alarm jack" on the top of the radio. Plug the microphone in and it breaks contact, un-plug the microphone from the RJ-45 jack and it redirects to something else....

I don't know enough about that setup to comment why or even if, that is the case.

 

[mmckenna]

It looks like they used an "alarm jack" on the top of the radio. Plug the microphone in and it breaks contact, un-plug the microphone from the RJ-45 jack and it redirects to something else....

That would be an RJ-48X, and I doubt they'd use those since it would short pins 3&4 and 5&6 when the mic was unplugged which would cause the other mic to not work.

It's likely a standard RJ-45. One 4 pair cable going to the mic jack on the front of the radio, and the other bridged through to the other mic position.

 

[domes]

I tried to find out the RJ-#'s for these parts. The best I can do is tell you that we buy them from Tessco and their SKU # and description:
SKU 17686 "Dual modular plug adapter" ( T ). I think they work but we don't buy them anymore because the male end is not long enough to snap in securely on KW radios.
SKU 497516 "modular coupler 8 conductor". Pin to pin straight through union.
SKU 483489 "Surface mount Modular jack 8 conductor". This has 1 jack with 8 screw terminals under the cover.

 

[kd4efm]

The KMC-9 was the 6 pin for the older TK 80 series radios, that is no longer in production
The KMC-9C is the "now" desk mic. Can be used with Analog and NXDN
the KMC-59C is for the use on DMR
Control Station Desktop Microphone (8-pin mod. plug)Note: Compatible with FDMA (analog / NXDN) and TDMA operations (P25 Phase 2 and DMR)
List Price: 180.00