[generalcrafts]

Control was turned on yesterday and the screen is full of the most random characters. I suspect it's a CRT control board problem, but would like to know if anyone else has had this happen??

[servtech]

Control was turned on yesterday and the screen is full of the most random characters. I suspect it's a CRT control board problem, but would like to know if anyone else has had this happen??

Could be a bad signal cable connection, random characters at least indicate the CRT is probably ok. Could be a decoder issue.

[nmcquiston]

There are different versions of that control. One has 1 main board on the bottom that controls everything with a crt control board on the side. The older one has several boards with the video processor on its own board. I have prints for everything if you want to go down the rabbit hole of troubleshooting it.

All the units I have repaired have been:

1.Power supply issues
2.Corroded pins on one of the Eproms
3.Typical CRT board problems.

Can you post a picture?

[generalcrafts]

There are different versions of that control. One has 1 main board on the bottom that controls everything with a crt control board on the side. The older one has several boards with the video processor on its own board. I have prints for everything if you want to go down the rabbit hole of troubleshooting it.

All the units I have repaired have been:

1.Power supply issues
2.Corroded pins on one of the Eproms
3.Typical CRT board problems.

Can you post a picture?

Here are a couple pictures. I looked over the entire board very carefully, all of the soldered pins looked clean, nothing out of the ordinary. No burned spots, no caps bulging or leaking, etc. servtech's reply mentioned it could be a decoder issue, which might make sense once you see what the screen display shows. I was planning on giving the board to someone with the capability to check each component, willing to try anything though to get this machine back up and running.

[nmcquiston]

It looks like you have the new version with the main board mounted remotely. The CRT board next to the tube is functioning normally, if it had a problem you wouldn't have characters. The board you are looking for is on the other end of that black multi wire cable hooked to the front panel buttons. It looks like the partial picture I attached.

Sorry I don't have a full picture on me.

The rom in the picture is the one I mentioned sometimes gets corroded. I can give you a checksum if you can dump it. 30 year old roms are near their end of life.

Also the two leds on the edge of the board should both be on for a normal POST.

You can also check the voltages at the test points. The voltages are printed on the silk screen.

If you can tell me the board model an rev number I can most likely point you to where the video encoding happens. My gut thinks cracked solder joint on an address line.

[generalcrafts]

***UPDATE - SOLVED***

It turned out to be the main board which is located inside the main cabinet on the side of the machine. When the video memory on that main board goes bad, the board needs replaced or fixed. We purchased a new board from Hurco and all is good. This was an AB7. Main board is 415 0124 500T

There are a couple options for transferring the memory over to retain your tooling and programs. 1st, do a main save at the terminal. You have to do this blindly since the display is no good, so I used the manual to see which menu numbers to press and did it that way. You can then pry out the memory chip and place it into the other board. For some reason the tooling didn't transfer with it when I tried and some things were funky, such as missing menu items. I hooked up a null modem cable and used a utility on the computer to make a backup, then, after swapping boards, copied the backup to the new board. Everything looked good, but the tooling still didn't transfer, so we had to manually enter them again, which wasn't a big deal.