Category Archives: Vintage

Sherwood S2000-III Tube FM Tuner Repair

Posted on January 8, 2015 by retrovoltage

Sherwood made some excellent hi-fi FM tuners back in the day, and this S2000-III is no exception. Unfortunately, there’s not a lot of documentation about this model available, but that didn’t stop it from getting an overhaul and alignment. The … Continue reading →

Posted in Audio, Electronics, Hi-Fi, Radio, Radios and Tubes, Vintage | Tagged , , , , | 1 Comment

Harman-Kardon Citation 17S Pre-Amplifier Refurbishing

Posted on January 2, 2015 by retrovoltage

I recently got to work on a Harman-Kardon Citation 17S pre-amplifier. Vintage HK gear is some of my favorite to work on: it’s robust, reliable, and built to be easy to service. The Citation 17 pre-amplifier is the companion for … Continue reading →

Posted in Audio, Projects, Stereo, Vintage | Tagged , , , , , , , , | 1 Comment

Merry Christmas from Retrovoltage!

Posted on December 25, 2014 by retrovoltage

Season’s Greetings!

Posted in Collections, Commentary, Vintage | Tagged , , , , , | Leave a comment

Sony TA-5650 VFET Integrated Stereo Amplifier Overhaul

Posted on December 18, 2014 by retrovoltage

I recently got to work on a very interesting piece of vintage stereo gear from the golden age of hi-fi in the ’70s, the Sony TA-5650 VFET Integrated Stereo Amplifier. It’s a little rough, and while the power amp section … Continue reading →

Posted in Audio, Electronics, Hi-Fi, Projects, Vintage | Tagged , , , , , , , , , | 1 Comment

Philco 42-365 Antique Radio Repair

Posted on December 15, 2014 by retrovoltage

This Philco 42-365 came to the shop in need of major repairs. It was missing its dial string, lamps, and the power transformer had melted down due to a failure in the main electrolytic capacitors. It’s melted and run everywhere, … Continue reading →

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VD-1221 Replacement Substitute Diodes

Posted on November 25, 2014 by retrovoltage

VD-1221, VD-1212, VD-1220, VD-1222, and many other vintage multi-junction diodes probe to failure, which are used in bias and RF mixer circuits, can be easily replaced by series combinations of 1N4148 diodes for reliability and longevity. Continue reading →

Posted in Audio, DIY, Electronics, Vintage | Tagged , , , , , , , , , , , , , , , , , , | 8 Comments

Vintage Schematic Mistakes

Posted on November 21, 2014 by retrovoltage

Every once in a while, you run into places where a drafting tech made some mistakes on the schematics. This one was a Philco 42-360 radio, which has the wrong tube called out in the tube line-up vs. the schematic. The … Continue reading →

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Harman/Kardon Control Amplifier A-401 Restoration

Posted on November 19, 2014 by retrovoltage

This little Harman/Kardon Control Amplifier, model A-401, just came through the shop for a full overhaul. It was in a pretty sorry state to begin with – one channel distorted, one barely gasping for air, and a world of scratchy … Continue reading →

Posted in Audio, Electronics, Hi-Fi, Projects, Stereo, Vintage | Tagged , , , , , , , , , , , , , | 8 Comments

EICO Stereophonic Integrated Amplifier HF-81 Repair

Posted on November 7, 2014 by retrovoltage

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 →

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Boes 901 Series IV Active Equalizer #241792 Refurbishment

Posted on November 3, 2014 by retrovoltage

Bose® 901 Series IV Active Equalizers are getting up there in years now, too, so more and more are coming up for repair. This one came in with a flickering power supply in need of an overhaul. Series IV was … Continue reading →

Posted in Audio, Bose, Hi-Fi, Projects, Stereo, Vintage | Tagged , , , , | 1 Comment