Digitac Help

[advancedcomm]

I have a digitac voter, we got into the programming once and set up most of the cards and seems to be working the way we need it to, but it is flashing the test light about once every second and can not seem to get into it thru hyperterminal, 3 of the 4 channels are set up the way i need them and seem to vote well, i am very impressed with the agc, but I can not get the first channel to work the way i need it to, I really need to get back into programming, as I said it worked once to do the original configuration but I still need to do some tweeking now to get finshed up, does anyone have any ideas, Ive tried 2 different null modem cables and 2 different computers with no luck, does anyone here have any ideas??
Any help would be greatly appreciated

[d119]

The test light blinking indicates a failure of some sort. How old is this comparator?

I've encountered a few DIGITAC comparators exhibiting this same sort of behavior, and it generally turns out to be a hardware failure on one of the input modules.

DIGITAC should be easy to connect to with HyperTerminal. 9600, 8-N-1, no flow control. Try using a null modem adapter. And of course, a DB25-DB9 adapter.

If you got in once, and cannot get back in with the same configuration (laptop, cable, etc) and your test light is flashing, I would suspect a hardware failure somewhere.

Can you connect to the other side of the DIGITAC? One side handles TX, the other RX. If you can get into one side but not the other, it's time for a FRU/depot trip on whichever card you can't access (provided you have verified it's not your terminal).

Where are you located? Perhaps I can help if you are nearby.

[Bill_G]

Agreed. A null cable and Hyperterm at 9600 8N1 should do the trick. Turn it off, reseat all the cards, plug in your laptop, and turn it back on. It should print to the screen it's current state.

[The Pager Geek]

I have also seen backplane issues that revert the baud rate to 2400. So if you do as Bill states and it spits out gibberish, try a different baud rate.

tpg

[advancedcomm]

I am not sure how old it is for sure, I purchased it from a radiosforsale and as i said it loaded fine the first time, I really dont know what else to do, does anyone have any parts sources or ideas on where the issue lies?, it has 2 channel cards and I only need 1,

Thanks

[advancedcomm]

Im sorry, I am in Illinois

[Bill_G]

Got the manual?

[advancedcomm]

yes I have a paper copy manual, bought from motorola, as I said I have it working pretty much the way I want it to but I can not seem to get back into programming to take care of the first channel, the other 3 work great and output is working well too

[The Pager Geek]

So you can talk to the other 3 ok, but not this one?

tpg

[wa6jbd]

The AGC chips are quite prone to failure, and may be the cause of the one receiver input not working. The chips are socketed, and it's simple to roll the chip in question to another input channel. If the problem follows the chip, replace it. The original AGC chips are NLA, and a replacement carrier board that fits in the chip socket is available for about $160. (!)