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Author Archives: jwk
Play Quake 1 on an Oscilloscope
Pekka Väänänen must have been bored over the holidays, as he came up with a fantastic and fascinating new use for an oscilloscope and a laptop: playing a round of Quake on his Hitachi V-422 scope in X-Y mode. After … Continue reading
Posted in Computers, DIY, Electronics, Gadgets
Tagged lofibucket, oscilloscope, quake, quakescope, vector, video game
2 Comments
Merry Christmas from Retrovoltage!
Season’s Greetings!
Posted in Collections, Commentary, Vintage
Tagged 1950s, christmas, hifi, merry christmas, vintage audio, vintage speaker
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Sony TA-5650 VFET Integrated Stereo Amplifier Overhaul
Cross-posted from the Rain City Audio Repair Blog: 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 … Continue reading
Posted in Audio, Electronics, Hi-Fi, Projects, Vintage
Tagged amplifier, bias diode, capacitor replacement, integrated stereo amplifier, overhaul, Sony, Sony TA-5650, stereo amplifier, varactor diode, VFET
1 Comment
Philco 42-365 Antique Radio Repair
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 42-365, antique radiov, philco, radio repair, vintage radio
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How Speakers Make Sound
If you’re looking for a great visual primer on how speakers convert electricity into the music you hear, check out this fantastic animated infographic by Jacob O’Neil at Animagraffs How Speakers Make Sound
Posted in Audio, Electronics, Ideas, Resources, Speakers
Tagged how speakers make sound, infographic
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Boxed Kit Amps’ Gobo Stereo Amplifier Build and Review
If you’re a subscriber to Nuts and Volts Magazine, check out my article in the December 2014 issue where I build, test and review the Boxed Kit Amps Gobo Stereo Amplifier, a great little desktop reference amp for any skill … Continue reading
Posted in Audio, Commentary, DIY, Electronics, Gadgets, Hi-Fi, Projects, Stereo
Tagged amplifier, boxed kit amps, gobo, nuts and volts
2 Comments
VD-1221 Replacement Substitute Diodes
We’re lucky that these days you don’t need to stock very many diodes in the parts drawers for refurbishing most vintage gear – pretty much everything except for the main power supply rectifiers can usually be replaced with some combination … Continue reading
Posted in Audio, DIY, Electronics, Vintage
Tagged 1n4148, amplifier, bias, diode, diode substitute, series, Sony, substitute, TA-4650, TA-5650, TA-8650, varactor, varactor diode, VD-1212, VD-1220, vd-1221, VD-1222, vd1221, VFET
8 Comments
Vintage Schematic Mistakes
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
Posted in Commentary, Electronics, Vintage
Tagged drafting, error, mistake, schematic
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Harman/Kardon Control Amplifier A-401 Restoration
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 a-401, amp, amplifier, circuit boards, control amplifier, harman/kardon, hi-fi, photos, pictures, rebuild, restoration, stereo, stereo pictures, vintage stereo
8 Comments
Watch a McIntosh Tube Amp Come to Life
Discovery’s How It’s Made shows us how a McIntosh vacuum tube audio amplifier comes to life: http://www.youtube.com/watch?v=2HgS6gvokEI Definitely worth watching!