Kenwood KMC-27 Microphone Damaged

[kenwoodgeek]

I have a quick question to put out there.

A few days ago I purchased a really crappy ham radio microphone clip with an adhesive back on it. I wanted to temporarily have a mount for my KMC-27. I installed the clip pretty well, made sure it was secure, and clipped the mike in place.

When I came back to my room a few hours later, the mike with the clip still attached was on my floor. The adhesive had failed. Luckily, the mic had only dropped about 1 1/2 feet onto my carpet which is pretty soft, but when I tried to transmit to make sure it still worked, I got a bit concerned. When I turned on the radio, the mike was making a slight buzzing sound, and when I shook it, I could hear something tiny shaking around inside of it. When I replayed the transmission on my scanner, it was nothing but a buzzing sound. Then, when I tried it a few minutes later, the mike stopped buzzing, and the transmission came through clear again.

What I want to know is if it's okay to still use the microphone. I have another microphone that I can still use that I have for sale on eBay, but I can take it down if I'm pretty sure the KMC-27 is going to crap out on me altogether. I want to know as soon as possible so I can get rid of the 27 and start using the other mike. One thing's for sure, I'm never using a adhesive clip again, and I did learn a lesson tonight.

 

[mmckenna]

Hard to tell. Most commercial radio microphones are built pretty well. They really tend to take a beating in a mobile environment. Dust, moisture, physical shock, etc. are all common occurrences in this environment. A 1 1/2 foot fall onto the carpet shouldn't be an issue, but it certainly could be.

Hard to tell what the buzzing was from your description. It's possible that it could just be that the transmitted RF was overloading the scanner and it's not related to the microphone at all.

One thing you could check is to make sure the cable is still fully plugged into the bottom of the mic. Removing the rubber boot at the base of the mic should expose the RJ connector underneath there. Wouldn't be unheard of for the drop to yank on that.

I'd hold off on selling that second microphone, though. I keep a few spares around for my mobiles since they take the brunt of the abuse. Having a spare on hand could be useful later on down the road.

Pretty much most adhesives will fail with time. Not always your best choice, but I understand sometimes you don't have an option. One thing I've found with anything that involves an adhesive is to make 100% sure that the surface you are sticking it to is clean. Wiping the area down with some alcohol works best. I keep a can of denatured alcohol in my shop for just this purpose.

 

[kenwoodgeek]

Thank you for the quick reply. You always seem to have the best advice.

That's what I thought, since I know radios don't always get treated the best, I didn't understand how it could have gave out that fast.

I temporarily programmed the radio onto a test frequency and put it on low power. I did take RF overloading the scanner as a consideration while I tested it, though. I did a test of both the KMC-27 and KMC-9C with the scanner the same distance from the radio. The KMC-9C came through crystal clear and the 27 still buzzed the third time I did it.

I did just make sure my connection was secure on the bottom of the mike, and it was. However, I did a couple more tests. After one test, it still buzzed, but I stretched the cord on the mike a little bit, and it suddenly came through clear. The mike itself stopped buzzing, too, yet I can still hear something rattling around inside of it when I shake it.

I just removed the other mike from eBay. That is really good advice, because I guess you can never know when you'll need a spare mike, and that's great thinking.

Furthermore, I will defiantly be more careful the next time I deal with adhesive. After rereading the ad more carefully, he basically mentioned the adhesive that came with the clip wasn't the best, so that was sort of my fault for not being more careful with it. I'm going to try to go with screws next time, though, since I know they really don't fail that often.

 

[mmckenna]

Could just be a chip of plastic floating around inside the mic. A careful disassembly would probably liberate whatever it is that is rattling.

Could just be a crappy connection in the RJ connector, either at the mic end or the radio end. Pulling on it might have just helped the connection seat a bit better.

While I have a number of Kenwood mobiles, my primary VHF radios in both vehicles are Motorola CDM's. I keep a spare microphone and antenna under the rear seat just in case. Never know when it'll come in handy.

 

[kenwoodgeek]

That's a good idea. I think I'll do a quick (and defiantly careful) disassembly of it tomorrow and see if I can find what's making the rattle. I'm hoping it won't be component on circuit board or something.

And yeah, as long as it sounds alright, I suppose I can deal with that.

That's a great idea. Defiantly smart thinking. Anything could happen. I've always "grown up" with Kenwood radios, so I've never seen Motorola base units. Do you think one brand is better than the other? Because I have been told Motorola makes better products than Kenwood.

I'm signing off for tonight, but I'll let you know tomorrow what I found in the mike.

 

[mmckenna]

Do you think one brand is better than the other? Because I have been told Motorola makes better products than Kenwood.

I'm signing off for tonight, but I'll let you know tomorrow what I found in the mike.

I don't think so, but there will be those that will argue that point. There are a lot of really good radios out there made by many different vendors. People have their favorites and there really can be a lot of brand loyalty. That's OK, I can understand that.
I've owned Icom, Kenwood and Motorola, as well as used a few different brands for work. Basically I find a radio that does what I want at a price I'm willing to pay. Some of those have been Kenwood, some have been Motorola. I wouldn't turn either one down.

I did just recently switch our PD over from all Motorola gear to all Kenwood. The comment I keep hearing is that the audio is much better on the Kenwood's.

 

[kenwoodgeek]

Sorry for the late reply.

And that's interesting. I suppose as long as it gets the job done, right? Haha.

I opened the microphone a couple days ago. Whatever is rattling around inside was not in the front cover, and I didn't feel like removing the circuit board to get to it, so as long as it's working, I'm alright.

We ran to Walmart over the weekend and picked up some 3M Command adhesive strips. I cleaned the wall and holder with rubbing alcohol, and this stuff seems to work a lot better. Mike has been in the holder for about 5 hours with no issues, but I'm still leaving my coat under it for the night just in case.

As I said, I have had no further issues with the microphone itself, so that's good. The dispatcher has been pretty much calling me daily for a quick hi, and she seems to be receiving well.

 

[mmckenna]

That should probably work just fine. Prepping the surface is key to getting adhesives to stick well.

Glad to hear the mic is still working well.