First, that broken track. I wasn't happy with the 'temporary' repair as it looked more like I'd thrown the wire at the board in the vain hope it would stick. One touch of the soldering iron and it was gone quicker than my wages the day after I get paid...
The permanent repair is, to be fair, pretty much like the old one but with a bit more care. I don't have any fancy replacement PCB copper traces as these are monumentally expensive and this is, after all, a bit of a hobby and not my profession. More's the pity as I'd love to spend all day fixing these things. Anyway, the track is fixed, on to the next thing.
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| Can you see the join? (Just to the left of the socket) |
Resistors. Nice and cheap from Tandy in the UK. It's a simple job of desoldering the old ones (including the temporary replacements I installed that may or may not have been the totally correct values) and then inserting the new ones. One advantage with new resistors is that they have nice long legs which makes it easy to get them into the board and then, by folding the legs out (or in if you prefer) underneath the board, they remain in place. This means you can get them all into the board in one go and solder them all in one go. The excess legs just need to be trimmed when it's done.
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| Folding the legs over |
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Resistors Replaced - and now correct values!
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Next.
Sockets. Each of these sockets cost 15p. Some purists may say the 500+ never came with sockets so why put them in now when a) they could cause connection issues that wouldn't happen if the logic chips were soldered to the board and b) it's a bit late. Well, these logic chips are still relatively cheap, but I'd much rather lose a total of 60p on sockets rather than the few quid I spent on the chips themselves if the board is beyond repair. Did I also mention I'm a bit of a cheapskate? Monetarily efficient is what I prefer to think. :)
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| New sockets |
From the photo above you'll also notice something is missing. The expansion connector was too far gone to be useful. It wasn't the worst I'd seen but for the sake of a few quid for a new one it wasn't worth the pain of trying to clean up the old one. New connectors are available still (which is more than can be said for the female A1200 expansion connector) but I won't order one until I know this board is fixed.
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| Sockets flush with the board |
A big hint for anyone starting out with soldering this type of component, be it socket or multi pinned chip. Hold them in place and solder opposite corners before you wade in and do the whole lot. If you don't your socket will end up at a funny angle and won't be flush with the board. I used a piece of masking tape on these which worked well. On my personal A500+, which I repaired a few months ago, I failed to do this and as a result there is a 74LS244 that appears to be making a break for freedom as one end is significantly higher than the other. Ooops.
Finally, I re-instated a link wire that I'd put on from one of the vias near the expansion connector to the jumper near the battery, to fix a potential additional track issue.
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| Link wire added |
So with the sockets in place and the resistors now the correct value it's time to get the chips in this board and plug it in.
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| Can we get past the green screen? |
I recorded the moment for posterity. (Do I really sound like that? Crumbs.)
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