On eBay Now...Vintage Leeds & Northrup No. 7661 pH Meter Vacuum-Tube Electrometer Lab Display For Sale
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Vintage Leeds & Northrup No. 7661 pH Meter Vacuum-Tube Electrometer Lab Display :
$185.00
Up for sale/sale is a beautifully preserved, highly complete vintage Leeds & Northrup Co. Catalog No. 7661 Vacuum-Tube Electrometer & pH Meter Assembly (Serial No. 398734).Manufactured in Philadelphia, PA, this mid-century scientific instrument is a classic piece of industrial laboratory history. Unlike many units found today, this example remains incredibly complete, structurally sound, and mechanically functional, making it a premier display piece for scientific collectors, decorators, or tech historians.🔍 Condition & Feature Highlights:• Excellent Mechanical Function: The side testing station door opens to reveal the original electrode bracket and mechanical clamp assembly. The bracket slides completely freely and smoothly up and down—a rarity, as these are usually seized by historical chemical exposure.
• Impeccable Rear Compartment: The rear battery and tube compartment is exceptionally clean. It features the original wood access panel, heavy-duty battery terminals, and vintage cloth-insulated spade-terminal wiring with absolutely zero signs of structural battery acid corrosion or wood rot.
• Abundant Original Glassware: Includes a vast array of vintage laboratory glassware. The vertical side slots house original reference modules, and the rear felt-lined compartment contains a row of intact spare glass electrode tubes. (One glass tube is shown held with gloves for scale; all glassware will be packed with extreme care).
• Stunning Aesthetic & Character: The heavy Bakelite faceplate features crisp text, an intact dual-scale (pH/Volt) galvanometer window, and a large main potentiometer wheel. To the right of the meter, a delicate, authentic hand-etched laboratory notation reads "Correction - 4", adding incredible historical character to the piece.
• Original Lid Schematic: The inside lid retains its complete, highly detailed graphic schematic and operating instruction placard for the No. 7661-A1 assembly.📐 Specifications:• Manufacturer: Leeds & Northrup Co. (Philadelphia, PA)
• Catalog Number: 7661
• Serial Number: 398734
• Cabinet Material: Original hardwood casing with integrated leather/canvas style handle and brass-toned hardware.📦 Shipping & Handling Note:This is a substantial, heavy instrument built with solid hardwood and heavy industrial components. It will be professionally packed, wrapped securely, and insulated with ample cushioning to guarantee the delicate internal glass components and casework arrive safely at your door.
Sold strictly as-is and untested as a historical scientific collectible/display item.
Too many requests.