Antarctica
Hot Rolled
- Joined
- Jan 16, 2007
- Location
- Annapolis, Maryland
I'd say I'm gonna fix this thing if it kills me, but I remember canoeing past a small boat one time with a dead guy in it, whose buddy explained that the dead guy had died doing what he wanted to do... He'd said that he was going to start that outboard if it killed him, and it did. So I'll not go there...
Spent some time on it again today. Pulled out the replacement mother board and put the original back in to compare some things. The original puts out a SMOKIN Hsync - like 40 volts, and the display works fine. Which tells me two things -
1) the 7407 driver on the replacement board is probably bad.
2) the cable is probably loading the crap out of the hsynch which is why the chip is driving it so hard, and it will probably kill this driver chip too (because the chip is only supposed to put out 30V)
I still can't get the replacement board out of "not ready" state, but then I can't read the alarms because the display still sucks.
But I also noticed something about the original board when I put it back in. When I switch the PWE stick to 'On' (write), I do not get a PS 100 alarm like on the other board. Its like the parameter write enable switch doesn't do anything, which is why I think it never re-initializes the memory.
I have no clue how to fix that yet, but I'll look at the schematic to see if anything is obvious.
Spent some time on it again today. Pulled out the replacement mother board and put the original back in to compare some things. The original puts out a SMOKIN Hsync - like 40 volts, and the display works fine. Which tells me two things -
1) the 7407 driver on the replacement board is probably bad.
2) the cable is probably loading the crap out of the hsynch which is why the chip is driving it so hard, and it will probably kill this driver chip too (because the chip is only supposed to put out 30V)
I still can't get the replacement board out of "not ready" state, but then I can't read the alarms because the display still sucks.
But I also noticed something about the original board when I put it back in. When I switch the PWE stick to 'On' (write), I do not get a PS 100 alarm like on the other board. Its like the parameter write enable switch doesn't do anything, which is why I think it never re-initializes the memory.
I have no clue how to fix that yet, but I'll look at the schematic to see if anything is obvious.
