Ultrakust-Gerätebau O. Raudszus, Rudolph Tietzsch GmbH & Co. KG, Firma Hirsch - Working tool (3) Industrial design - Ultracheap „Thermophil“

Consolidated Collection: Vintage Ultrakust “Thermophil” Precision Thermometer Set + Historical Analog Indicator Instrument + Rarity for Collectors & Tech Enthusiasts

For sale is a fascinating, historic bundle of analog measuring instruments from the renowned Ultrakust brand “Thermophil,” dating to the mid-20th century. A true piece of German industrial history in authentic original condition!

The set stands out with its massive construction from Bakelite and wood, as well as the beautiful mechanical aesthetic of the analog needle instruments. Perfect as a decorative collectible, for historic workshops, laboratories, or museums.

The devices in detail:

Ultrakus t “Thermophil” Analog Main Unit
• Manufacturer / Era: Ultrakust Instrumentation (Thermophil series), approximate late 1950s / 1960s.
• Casing: Classic, deep-black Bakelite housing.
• Controls: Rotary switch for “On,” “Oak A” and “Oak E” for precise zero-point and end-value calibration of the analog mirror scale.

Separate Thermophil Control / Calibration Module (Type H 10 AO)
• Model / Serial number: H 10 AO / A.Nr. 449698
• Features: Small, square auxiliary module with an analog dial for the temperature range 0–210 °C.

Classic Insertion / Probe Temperature Sensor
• Form: Ergonomically shaped, ball-/drop-shaped plastic handle with long, sharp metal probe – compatible with the Thermophil system.

Tietzsch Vintage “Rubber Test Ball” Voltage Tester (up to 500V)
• Manufacturer / Era: Rudolph Tietzsch GmbH & Co. KG, circa 1950s to 1960s.
• Material & Housing: Legendary, extremely rugged and impact-resistant solid rubber body (no Bakelite!). Sits heavy and secure in the hand.
• Technical data: Nominal voltage range up to 500V with clearly visible historic VDE test mark. Designed for a maximum on-time of 5 minutes.
• Condition: Very nice original condition, the rubber shows a great authentic patina. The glass over the analog display is intact.

Hirsch Laboratory & Darkroom Time Switch (0–60 seconds)
• Manufacturer / Era: Hirsch (known for the unmistakable logo with the jumping deer on the dial), circa 1930s to 1950s.
• Housing: Rustic, dark wood/metal enclosure with rear power cord.
• Function: Mechanical exposure timer for photo labs to precisely control exposure times. The side lever is used to wind or start the precise clockwork.
• Aesthetics: Outstanding industrial look that immediately catches the eye – a brilliant decorative piece.

• Condition: The devices are in optically good, undamaged vintage condition with age-related signs of use (see photos).

• Functionality: The devices have not been tested for functionality due to lack of test gear and their historical age. Sale is explicitly as a collectible object, decoration, and hobbyist item, with no warranty.