Category Archives: Vintage

1960 Grundig SO191 Stereo Hi-Fi Console Repair

Posted on February 27, 2015 by retrovoltage

Updated July 2026 with some additional photos from the archive, and schematics at the bottom. This was a pretty early repair from back in the shop days so there’s a few things I’d do more cleanly for a customer today, … Continue reading →

Posted in Audio, Hi-Fi, Projects, Vintage | Tagged , , , , , | 31 Comments

Bose® 901 Series VI Active Equalizer #199732 Repaired

Posted on February 20, 2015 by retrovoltage

A first for my shop, I recently worked on a Bose® 901 Series VI Active Equalizer! These are considerably newer than the Series I-IV that typically come through the shop, although they’re still getting to be 25+ years old at … Continue reading →

Posted in Audio, Bose, Electronics, Projects, Vintage | Tagged , , , , , | 1 Comment

Philco 39-45 Retrofit to 40-201 Cabinet Vintage Radio Repair

Posted on January 16, 2015 by retrovoltage

A neighbor approached me with his family’s Philco 40-201 vintage radio to be restored back to working condition. It had sat for several decades, very well preserved, but ultimately needed some service after the years. Very unfortunately, however, the original … Continue reading →

Posted in Electronics, Radios and Tubes, Vintage | Tagged , , , , , , | 2 Comments

Harman-Kardon Citation 12 Deluxe Professional Power Amplifier Refurbishment

Posted on January 12, 2015 by retrovoltage

Matching the Harman-Kardon Citation 17S professional pre-amplifier shown previously, this Citation 12 Deluxe power amplifier is its 120W per channel companion. It came to the shop for a preventive rebuild after serving for quite a few years. The owner had the … Continue reading →

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

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 →

Posted in Projects, Radio, Radios and Tubes, Vintage | Tagged , , , , | Leave a comment

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