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Full Version: Strange addition in a 41CX
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I recently sold a friend an HP41CX. He called me today to say that the CX had an extra capacitor attached to the area where the battery charger plugs into and also that when he presses Cat. 3 the machine flies through all the symbols, at a greater speed that his second CX.
Could this be a speeded up 41CX?

That sounds like an overclocked 41. I have several CVs that were hacked to run at 2.3x normal speed, but most speedups are more modest - 40% is typical.

I'll bet that what looks like a capacitor in the charger port is actually a magnetic reed relay. Bring a fairly strong magnet near it and see if the speed changes. Some machines have a toggle/latching circuit on the reed relay, others need the magnet there all the time to change the speed. Also check the "BEEP" command. It is usually the easiest way to detect the speed change.