Today was the monthly Electronics Flea Market in Cupertino, and we came across some gems this month.
Above, an AN-OIL-IZER. The seller said her geologist father used it for testing oil purity.
It’s described in patent number 3182255, a device for capacitively testing lubricating oil (e.g., engine oil) for contaminants, by looking for changes in its dielectric constant. To use it, you place a drop of the oil in the holder, and the ball bearing into that drop of oil. The bearing is held down by a leaf spring, keeping it indexed against the holder. This forms an oil-filled capacitor between the ball bearing and a lower curved plate that is insulated from the bearing. The capacitance will vary as the dielectric constant of the oil changes due to contamination. It comes with two ball bearings, as well as oil samples for calibration.
The E-Z-Code Jr. is a tool for learning morse code: when you draw the “electric pencil” through the slots, it crosses contacts in the correct spacing to make the characters. It also has a hinged telegraph key which can be tucked away below the device.
The seller of the E-Z-Code Jr. told me that the thing I really should be photographing was this magnetron. It is a beautiful old piece of hardware, with its wave guide and high-power tube.
I’d love to see the circuit diagram for the Cosmic Energy System by Psy Herabel [sic] Health Town, Inc.! (Sadly, their domain no longer seems to be active.)