And conversely, I've never seen a CC with a 4.5V alkaline battery on board. I am intimately familiar with five CCs, two of which are Performa 250s, but all are 1993 (Apr., May, Sep., Oct.), and all have provision for the usual half-AA 3.6V lithium. So also did the fifth, which now lives with Kallikak. The only significant variation that I have seen is the presence (not just the solder pads) of a CUDA switch on one of mine.

The nominal lifetime of the CC was Feb. '93 to May '94, which gives the 4.5-V variant a lifetime of about two months, at most.

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