Texas Instruments TI59 weird card problems

[voltaage]

(11-03-2021 02:01 PM)Ren Wrote:  

(11-01-2021 01:10 AM)voltaage Wrote:  Also I had to remove the varnish of the sheets and sand them a little bit

will put an unopened beer can into a bowl of Hydrochloric (?) Acid to about midway up the can.

Whoah that is quite impressive. Certainly I don't have those chemicals at my reach. The can I used to make the contacts was an unbranded starbucks cookie straws container (like an OEM product: only sold for their franchises). Both sides (inner and outer) were covered with that thin plastic lacquer of some sort, but there was no label paint as you would normally encounter with soda cans. That made the job easier since I only had to remove the film with lacquer thinner, then sand them to make the surface conductive.

I don't think that is the problem beacause I also tested my calc with a power supply: same results. Also as I mentioned earlier that can is way more thick than alluminium tape, which I used to in the initial rebuild.