My Minolta DiMage A1 displays

If you're lucky, the CF card is faulty. It's going to be a very old card now if it's the original one supplied/bought with your A1. You've never upgraded to a larger card in all this time so it suggests you've never needed to. 128 and 256mb cards are virtually worthless now, so I'd be amazed if you couldn't get one for free via Yahoo FreeCycle. You can also try reformatting your card in a card reader/writer, but A1's and A2's often won't recognise a card formatted in this way and it can render them permanently unreadable by all A1/A2/A200 cameras.

If you're unlucky, then you've bent or broken one or more of the pins inside the card slot which connect to your card when you insert it. To check, get a bright torch and look down inside the card slot. Any bent pins will be self evident as there should be a neat double row of pins and missing pins will show up as gaps.

If you have bent pins then you've nothing to lose by trying to carefully straighten them, if you can't or if the pins are broken, then your camera is effectively irrepairable. Scrap A1's and A2's can both provide the part, but retreiving them from the donor camera is really difficult and so far I've never managed to refit one successfully and I've done a few now. A pro repair is simply not cost effective, especially when a perfectly good used A1 goes for around £40-£50 and the better A2's go for around £80-£100. If you're in North America you can expect prices to be even lower.