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Tag Archives: hf-81
EICO Stereophonic Integrated Amplifier HF-81 Repair
From the late ’50s, I had this nice example of an EICO HF-81 amplifier come through my shop. These are nice little stereo amplifiers with a built-in phono pre-amp and RIAA equalization and feature about 14W of power output per … Continue reading
DIY Replacements for Vintage Couplets and Printed Electric Circuits
Starting in the ’50s, they’d figured out how to start miniaturizing components. “Couplets” and “printed electric circuits” started showing up in equipment around then. These components were combinations of several resistors and capacitors in a single package. Like most components … Continue reading
Posted in DIY, Electronics, Ideas, Vintage
Tagged centralab, couplet, crl, eico, hf-81, pc-191, printed circuit, printed electric circuit, Sprague, tc-24, vintage circuit
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