Maxtrac blanking assistance needed

[Rick Rock]

I have a maxtrac 50 that is giving a low tone for 5 sec on powerup, which indicates a corrupt codeplug, and the radio won't read. It comms good, and on the read, it will come on showing reading codeplug block 1 of 64, then it gives me a serial buss error. I have L05.03.00 and I need to get it back into service. HELP!!!

[kb0nly]

So Lab gives a serial bus error when trying to blank it?

[kcbooboo]

Could be the serial programming interface transistors. I saw one where they got blown to bits. I think one is an NPN MMBT3904, and the other is a PNP MMBT3906, both surface mount. You'd have to troubleshoot it with a scope or voltmeter by applying +5v or ground to the programming pin input and watching what comes out the other end, at the microprocessor.

Can you access the radio at all in any of the service modes, i.e. try changing the warp setting by one value.

Bob M.

[Rick Rock]

It will seem to take warp adjustments, but then it gives a serial error, but when I exit out and come back to it, the value is @ the adjusted value.

[kcbooboo]

Can we rule out that you're running the software on a machine booted with DOS, i.e. you're not running it from a Windows environment? That will play havoc with serial communications on the older programs.

Bob M.

[Rick Rock]

Its a Toshiba Satellite T1910 486 running DOS only, no windows whatsoever. Woody99 suggested that it might be a BUS speed issue...

[kcbooboo]

I've used Pentium laptops at 100 and 850 MHz with no problem at all. I do recall that some programs, maybe RADMBL, had a timing value in the PC Setup (main menu F9) screen, but I haven't had to play with it recently.

Of course it could still be a bad RIB or even a bad computer, so you should try substitution: another radio, another RIB, another computer.

The microprocessor's crystal could haved changed frequency, as it would need to run at a particular speed for serial communications to work properly.

You could send the radio to any number of people (myself included) who could put it into a known working environment to see if they can blank it. If not, then the easiest thing to do is replace the logic board and start fresh.

Bob M.

[Max-trac]

Is that setup workin on other Maxtracs OK??

What's it do if you blank it and reinitialize?

[Rick Rock]

Is that setup workin on other Maxtracs OK??

This is the only maxtrac I have access to.

What's it do if you blank it and reinitialize?

That is what this post is for- I can't get that done!

[Max-trac]

You are getting the error right at the end of a proceedure to access the radio.

Double check the wiring of the programming cable;
http://www.batlabs.com/images/maxpin.gif

I suspect something amiss with your setup and not the radio.

I can work on it or upgrade it for you....

[TWEMARS]

The problem might be a defective DRAM (Dallas something or other...it's like an IC but it's a block and it's about ¼ inch thick).

Just replace the firmware with a Maxtrac v4.0 P/N HLN9277A, blank it again and then try to program the radio.

I have done this in the past and it cured the beep.