Error Programming MT2000 (ACK/NAKed error)

[Duster]

Hello,

I have tried the search function and reviewed all the posts that come up, but cannot find any kind of helpful answer to my question, so here goes, one more time:

I am trying to program a UHF MT2000. I am using a P-II 233mhz laptop booted into true DOS, a true RIB, and a factory cable. I have programmed several MT2000s, MTS2000s, HT1000s, and VISARs (both VHF and UHF)from this laptop and this setup (obviously with different end-cable for the VISAR). I have several versions of MTSX (legaliy), up through 06.07.

This radio (and only this one) will not read, using ANY version of MTSX that I have. I receive the following error: "Request not ACKed/NAKed error". I also received "Checksum error" once or twice, but the ACK/NAKed error is the pre-dominant one.

Additional background on the radio, most of which I discovered by investigation and testing: I purchased the radio on *Bay, allegedly legally surplused from a large petroleum company in Alaska. The programming in the radio currently appears to use some kind of encryption, as the rotary ring activates the "square" indicator on the screen, which flashes and then times out after several seconds. The radio will open a carrier when the PTT is keyed, but the mic is not live; ie, no voice is heard when listening to the channel (I discovered the programmed channels using a scanner with Close Call), either using the built-in mic or one of several remotes/lapel/surveillance mics that I use. I am wondering if the mic is inhibited by the encryption programming, or if there is something wrong with the radio. I gave the radio to an acquaintance who is a professional radio technician for the same government agency who employs me, but he got busy on a project and was unable to tinker with it.

My questions are:

1. What does this specific error mean?
2. How do I combat/mitigate it?


Thank you in advance...

David

[N6LAU]

Hmmm... One thing that comes to mind is possibly faulty flex assembly in the housing. Could explain the communication errors with the RSS as well as the mic not working. Do you have a known good housing that you can put the radio in to rule this out?

Joe

[Duster]

I have one VHF MT with the same case (full feature keypad and front display), and another UHF MTS with a top display. I have had the other UHF apart, so I know how to disassemble it.

By changing the 'housing', do I understand you to mean that I need to disassemble the radio, disconnect all the flex ribbons, and put the 'guts' of the radio into the known good case? I can experiment with that this weekend. However, would that problem also keep the mic from working when used remotely, such as from a speaker mic or a surveillance mic?

What does that ACK/NAKed error mean/indicate? I haven't found anyone who can explain what that error means...

[nrembis]

ack/naked error is hardware failure in your link to the radio....means software doesnt even see the radio, you said cable and rib program fine on other radios, so that narrows it down to this particular radio.....contacts not clean, broken flex.....who knows??? you will just have to dig in and find it.

[Pump3]

Clean the side contacts with an eraser, take the radio apart and make sure everything is seated correctly

A flashing square indicates the radio is in program mode, ie scan list program

If it were encryption it would display a "Ø" on the display

[Duster]

Thank you for the replies; clear, concise, and very explanatory. I start days off tomorrow, so I will disassemble the radio and start troubleshooting. I'll post any findings for future questions. Thanks again!!

[N6LAU]

I have one VHF MT with the same case (full feature keypad and front display), and another UHF MTS with a top display. I have had the other UHF apart, so I know how to disassemble it.

By changing the 'housing', do I understand you to mean that I need to disassemble the radio, disconnect all the flex ribbons, and put the 'guts' of the radio into the known good case? I can experiment with that this weekend. However, would that problem also keep the mic from working when used remotely, such as from a speaker mic or a surveillance mic?

What does that ACK/NAKed error mean/indicate? I haven't found anyone who can explain what that error means...

Correct. Pop the radio out of the housing, disconnect only the flex ribbon that goes from the housing to the radio, and pop it into a housing of the same flavor (same display type, keypad if any, etc.) that you know works good and see if it works then. And yes a problem with the flex inside the housing could cause problems with the accessory connector not working right as the flex is what connects that to the actual radio.

The eraser thing would be a good thing to try prior to switching out housings as well.

Joe

[Duster]

Progress!!!

I swapped housings on the radio, and the radio read properly. Success!

Now, how do I fix the problem in the other housing, since I don't actually have a 'spare' housing, and the test radio is also an in-service radio?

Is it repairable, or is it more of a "find a parts radio on eBay and hope for the best" kinda problem...?

[Duster]

Update: While I had the radios apart, I also cleaned the contacts on any flex cable or exposed copper points I could find. I finished programming the UHF while it was in the test housing, and then put the VHF radio (the housing I used to test the UHF) into the questionable housing. It now appears to be working normally, so perhaps it was simply a dirty contact, or a poorly seated cable connection. I will play with them over the next few days, but it looks like the problem may be fixed.

Thanks to everyone who helped me out!!! I learned some new diagnostic skills for the Jedis, and I'm sure I will use them again.

Thanks again!!

David