As Mike Wilhelm noted, TOCOS is a Japanese manufacturer, that has a North American office (Northwest Chicago suburbs) not far from my QTH.
TOCOS RA25 Wire Wound Potentiometer (designed for Panel Mount) “25” references 25mm (1 inch) diameter, made by CTS (Elkhart, IN) over past 100 years. https://tocos.com/products/series/wire-wound-panel-controls/ra25
DATASHEET for TOCOS RA25 https://tocos.com/uploads/media/products/0001/01/1256394e7e05d3b089a35ad5889...
SELECT Your Country, State/Province for TOCOS Distributors https://tocos.com/sales-locations
TOCOS America 1177 East Tower Road Schaumburg, IL 60173 Telephone: 847-884-6664 FAX: 847-884-6665 Sales e-Mail: sales@tocos.com Web Site: http://www.tocos.com — greg, w9gb == From: "Joseph B. Fitzgerald" jfitzgerald@alum.wpi.edu To: "amsat-bb@amsat.org" amsat-bb@amsat.org, Rafael Pena pinoleronica@hotmail.com Subject: Re: [amsat-bb] G-5500 AZ Potentiometer
I didn't find a supplier, but I did find a datasheet. You can probably find a replacement from a different manufacturer. Curiously it is only rated to -10C. https://www.tocos-j.co.jp/tocos-j-wp/wp-content/uploads/2019/06/RA25_Series....
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