TK-8180 Programming Issue

[kenwoodgeek]

Hello, everyone.

In today's useless adventure, I'm attempting to reprogram one of my company's old TK-8180H units which has not been used in years and has only old channels.

The problem is it will not communicate with KPG-89D. When I attempt to read or write the radio, I just get the "Check comm port" etc message. The radio shows no sign of even being connected.

I can plug another radio into my cable right after and it will work fine. Just for the fun of it, I tried reading with SJ-180. Nothing.

The pins of the connector on the front of the radio are in excellent shape and free of corrosion. I removed the control head and checked the ribbon cable which has a good connection. The radio does transmit when I plug in a microphone and key it.

Any simple fix, or is it another paperweight?

Thanks!

 

[mmckenna]

A couple of things you can try:

Make sure it is a US market radio and not something some dude grabbed off e-Bay because it was cheap. Unlikely the cause, but it's worth a check.

Disassemble the head and make sure the flex cable is well seated.

If that don't fix it, consider giving up. These radios are getting cheap and not worth putting a whole bunch of time into unless you just want the challenge (and you probably do).

If you wanted to get saucy with it, you could try programming it via the rear DB-25. I think that will work with these models. I know it will with the NX-#00 mobiles….

 

[ramal121]

The usual suspects are what you have already covered. Maybe double check? The other thing to try is a regular 25 pin serial cable to the back of the radio (if you have cables hanging around).

 

[kd4efm]

db9 to db25, plug into the back of the radio, try reading it that way too....

 

[kenwoodgeek]

Thank you, gentlemen. While I don't have the DB25 cable to program from the back (I need to get more old school for that, haha), I decided to try swapping the head from another 8180. That immediately fixed the issue, and I could read the radio.

Putting the original head back on made the issue come up again, so I figure the head either has a loose connection or possibly a fried component inside, but I didn't notice anything from just uncovering the circuit board.

The radio is excess (and will be useless whenever we get the NXDN digital upgrade they keep promising us will happen), so I'll hold onto it and see if another 8180 fries and can spare its head. Otherwise, when I have some free time, I want to tinker around with this head and see if I can find where the disconnect is.

 

[mmckenna]

RX Data, the data coming from the computer through pin 7 of the RJ-45 has a few chip resistors in the path to the CPU. That pin is also used for the hook switch function on the microphone. I'd check for someone running a jumper from that pin to ground to force the hook switch function if they had the mic disconnected. Possible, but would be weird since that can be done in software. But we've seen techs do weird things.

If the hook switch function works, then at least part of the circuit is good. There's some transistors that handle the trade off between hook switch functionality and the RX Data function. Could have become boggered. Since doing the surface mount stuff is nearly impossible unless you have all the right stuff, I'd look for something out of place on Pin 7 of the RJ-45. If you don't see it, move on as it likely won't be an easy fix.

 

[AM909]

People have also been known to protect a radio's programming via cutting a trace.

 

[AM909]

I suggest posting a hi-res photo of the two sides of the board (or you may have to upload them somewhere and post a link).

 

[natedawg1604]

People have also been known to protect a radio's programming via cutting a trace.

So how do they program it afterwards? How would that work?

 

[mmckenna]

So how do they program it afterwards? How would that work?

You don't.

But in the case of this radio, you'd just use the rear DB-25, unless the tech was smart enough to disable that, too.

Glad most newer radios have passwords on the read/write...