67 is flakey

[John Garza (3665)]

Yep, Teenix is right.

* Visual inspection with a magnifier will spot corrosion. 5-10X will do.

* Caps die eventually, so replace them all.

* Though rare, chip plastic and ceramic can crack over the ages, leading to a path into the central area with the silicon chip and fine wires, where atmospheric humidity and chip lead corrosion will take it's toll. Or normal aging can occur without cracks. If you have another working machine, try swapping chips to determine if one (like the ACT) is the trouble.

* On the Classics (like the 67), it's pretty rare to get corrosion spreading from the battery compartment to the CPU card, as the battery area is well sealed and electrically connected with lengths of wire. Unlike Woodstocks, where the PC board fingers reach out to touch the battery contacts, inviting corrosion to immediately spread to the traces.

* One of the known failure modes of the ACT chip matches your symptoms - the need to 'warm up' before operating properly. If the ACT is bad, it will have to be replaced either with an ACT from a donor machine or a Panamatik replacement unit. Sometimes a 20K resistor across pins 11 and 12 will help stabilize it. But it's no guarantee if the unit is too far gone.

Hope this helps!

-J