HP-25 Isopropylalkohol

[Frido Bohn]

(04-06-2022 04:56 PM)Tom Flatterhand Wrote:  After a test with a lab power supply and test clamps on the rivets of the contacts it could be brought to life. With a nail file I have then filed the battery contacts something and now he runs.

Just as a reminder in the case that you don't know that the Achilles tendon of the HP25 is the use of external power supply without batteries being in place. The use of power through the battery contacts is fine but beware of applying power on the contacts at the bottom of the chassis without batteries that serve as a kind of overvoltage/overcurrent buffer.