TK-7180 no audio problem

[devile]

Hey All,

I have two TK-7180's... Both with the exact same programming. However, one of them when you key up the mic it does transmit, however it isn't transmitting any audio, just noise. We have tried with tested working mics (ie the same one on the other radio) and same result. Sometimes you'll hear a word come through the noise, but for the most part it doesn't work.

Anyone have any idea as to what could be the problem?

 

[N2AL]

How much power are you running? It is possible they are so close that they are desensitizing each other.

 

[buddrousa]

It is also possible that it is that far off frequency

 

[jim202]

I would make sure your using a simplex or talk around channel when your doing the audio testing. Use of a service monitor will provide the information your radio is providing you.

Is there a chance someone has got their fingers inside the radio and messed with some of the adjustments?

The radio could be off frequency.

The radio could have a bad mic connection.

The mic gain could be turned down or set wrong.

Your to the point where a service manual and a scope are what you need next to follow the lack of mic audio.

 

[devile]

When testing extemely close with a portable it works almost 100% reliably, but when testing with other land use mobiles further than 20 feet away and we get the result of the above.

Running 25 watts (or whatever the high setting is).

Nobody has been in the radio since it worked.

Testing other mics from other working radios, same problem.

 

[buddrousa]

DID YOU CLONE THE SECOND RADIO? YOU MAY HAVE SENT IMPROPER TUNING DATA TO THE SECOND RADIO.
Always read change and program each radio. NEVER read one radio and program several radios from just one radio.
If you do not own a service monitor other and test equipment it is time to take that radio to the shop for repairs.
1. Is it on frequency test with service monitor not another radio.
2. Test the power out to a watt meter on a dummy load not guess because its the model number.
3. Does it receive the programmed frequency sent from a service monitor not another radio.
4. What does the service manual say the test specifications are TX RX current draw ect.

 

[kayn1n32008]

When testing extemely close with a portable it works almost 100% reliably, but when testing with other land use mobiles further than 20 feet away and we get the result of the above.

Running 25 watts (or whatever the high setting is).

Nobody has been in the radio since it worked.

Testing other mics from other working radios, same problem.

Are you using a simplex channel or on a repeater?

 

[devile]

Simplex Channel...

It was cloned, or something as it has the same program as the others, but it has worked for a while since it's been programmed.

I maybe just need to take it to a shop if it's clearly nothing I can do...

 

[buddrousa]

I would invest in a bird 43 watt meter with 50 watt and a 5 watt slug. That way you know your antenna is good and not burning your PA up.

 

[devile]

I tired with another antenna, same problem... The I confirmed it isn't a clone, just channel programming dropped onto it. I'm thinking something broken at mic plug as the mic will key, but no voice comes through, and is intermittent regardless of what mic is connected.

 

[N2AL]

I tired with another antenna, same problem... The I confirmed it isn't a clone, just channel programming dropped onto it. I'm thinking something broken at mic plug as the mic will key, but no voice comes through, and is intermittent regardless of what mic is connected.

Have you tried using a different microphone to see if that corrects the issue?

It may be something inside the radio if another microphone produces the same results.




Andrew | N4AWL
www.n4awl.com

 

[buddrousa]

I would look for a broke mic jack or a bad solder joint in the audio board.
Just a thought does it pass RX audio?

 

[n5tbu]

DID YOU CLONE THE SECOND RADIO? YOU MAY HAVE SENT IMPROPER TUNING DATA TO THE SECOND RADIO.
Always read change and program each radio. NEVER read one radio and program several radios from just one radio.
I .

That was a Motorola problem,Kenwood doesn't clone tuning alignment.
mod

 

[devile]

Good no tuning alignment issue, thanks.

Tested with known working mic, same problem.

Not sure what RX Audio is.

I plan to open up the radio as soon as the truck gets back from working to look for a broken solder somewhere.

 

[buddrousa]

RX is receive. Does it hear audio if you key another radio does it hear the other radio.
TX is transmit.

 

[devile]

Yes, it receives clear as day on all freqs.

 

[ramal121]

You didn't change the settings of the modulation line in programming somehow did you?

 

[buddrousa]

I am back to thinking Transmit Power or Mic Jack Problems.
If you are 2 or 3 blocks away and key this radio do you receive any thing on the good radio?

 

[devile]

Thanks for all the help guys... It was a weak connection at the antenna causing the issue to be intermittent. Problem solved.