Sigh. So, the digital medal has problems. Not the least of which is the time and energy I have available to work on it. The worst problem is the damn hole sizes. I trusted the print out as a sort of eye-ball measurement that all the hole sizes were OK. They weren't. I have to drill out a lot of holes. The worst of that is for the LED displays that can't be soldered on both side. I have to drill a second hold very close the pad and run wire-wrap wire through it and the main hole to get a good mechanical and electrical connection to both sides of the pad.
The next problem is the third transistor array that was thrown in at the last minute. I guess I miscommunicated with the fellow who did the schematic for me. I though I had understood him to say that he'd prototyped the circuit. He hadn't done it for this last minute add. First I discovered that power was backwards. I should have looked more carefully once I discovered that. But, no. I started on a second drilled out board only to discover that the inputs and outputs were also backwards.
So now I'm onto to the third drilled out board. Ironically this board is a touch easier because I don't have to cut traces to fix the power. Since the inputs and outputs on the UDN2981 were also reversed, if I solder the chip to the other side it will be connected perfectly on the current board. If this works I don't think I'm going to edit the board except for hole sizes.
Anyway, I should be able to get a bit of work on it tonight. Maybe I'll be able to light it up, who knows. *I WILL* get it working for the November games dammit.
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment