Make sure you don't have a short circuit somewhere (soldering tin or small pieces of cut wires)
Remove all batteries (backup battery included), press "ON" about ten times and wait a few minutes. Put the batteries back in and try to start the calculator again.
If this doesn't work, try this: Take out all batteries (backup battery too) and make a short circuit: connect P1 and P4 with a wire and wait a few seconds, remove the wire, put the batteries back in and turn the calculator on again.
-------------------------------------------------- | | | ~~~~~~~~~~~~~~~~~~~~~ | ~ P ~ | ~ 1 ~ | ~ ----------------- ~ | ~ P ~ | ~ 2 ~ | ~ ----------------- ~ | ~ P ~ | ~ 3 ~ | ~ ----------------- ~ | ~ P ~ | ~ 4 ~ | ~~~~~~~~~~~~~~~~~~~~~ | --------------------------------------------------
If your calculator still doesn't work, try to restore the
original configuration: remove the 15pF cap and put back the old
C7 (27pF)
If this is working you may try to use 18 or 22pF instead of 15pF.
This is more stable but makes the TI "only" about 1.5 times as
fast as with the original 27pF.
Michael Melgares <spyder@iwl.net> suggested to do this if you don't want to short circuit your calculator: Take out the batteries and put in some new ones. Once this is accomplished you can turn it on. Then you send your calculator (if your calculator can't get into the link menu) a mem backup. This should give you an error message. This time you should be able to get into the link menu and give yourself another memory backup and you are set.
Note: Please don't e-mail me if something goes wrong, I'd like to help you, but I'm quite busy and I couldn't do anything else than telling you what I have already written on this page, sorry.