SBC6120 (a build-it-yourself PDP-8 clone) Last Buy and End ofLife

[Don Y]

dave06a at dunfield.com wrote:
>>> Anyway, reseating chips isn't that difficult of a "fix" anyway...
>> Well it beats replacing unsocketed chips any day. Swap-in/swap-out vs.
>> cut pins off/desolder/clean holes/install new chip/clean more
>> holes/install/solder/resolder the pad you missed....
> 
> IMHO, and essential tool if you are serious about doing any kind of
> rework is a good desoldering station. Takes a bit of time, but if done
> it right, the chip just lifts out with no damage to it or the board. One
> of the best investments to my workbench that I ever made....

This only seems to work on "nominal" boards -- 4 layers or
less, respectable annular rings, appropriate thermal reliefs,
etc.

Get a board with fine line rules and lots of thermal mass
on a pin (e.g., an internal power plane that is not
relieved) and you'll stand a good chance of lifting pads,
regardless.

This actually can work to your advantage if you are
designing products and don't want folks dicking with them!

<grin>