ANTIQUE HARTMANN & BRAUN GERMANY TELEGRAPH INSTRUMENT | #164024373
Hartmann & Braun Multavi R Voltmeter - OD&D
WW2 German, Soviet, Allied militaria, uniforms, awards, weapons history. War relics forum
ENGLISH MANUAL for Pontavi Portable Wheatstone bridge, Hartmann/Braun | eBay
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Complete Catalogue of Electrical Measuring and Test Instruments Manufactured by Hartmann & Braun : Electrical Engineers at Bockenheim-Frankfort O/M (Paperback) - Walmart.com