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Author Archives: retrovoltage
The New Stewart-Warner Series 900 Radio
This Consolette Ensemble combining Stewart-Warner Table Cabinet Receiver with the New Stewart-Warner Dyphonic Reproducer, an arresting value at $113 (less tubes). Radio Retailing, April 1929
Posted in Collections, Vintage
Tagged consolette, dyphonic, radio, radio retailing, series 900, stewart-warner, vintage ad, vintage radio
1 Comment
Yamaha B-2X Check-Up and Adjustment
I recently had this Yamaha B-2X through the shop. It’s a massive beast of a power amplifier from the late ’80s, delivering up to 170W per channel with 0.002% THD. Being somewhat more recent, this one just needed a quick … Continue reading
Posted in Audio, Electronics, Hi-Fi, Projects, Stereo
Tagged amplifier, B-2X, yamaha
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Extracting Screenshots from the HP 3585A Spectrum Analyzer
I’ve posted a few times about my HP 3585A spectrum analyzers over the past several months, and after chipping away at the problem I’ve finally solved the screenshots issue! It boiled down to a bad GPIB cable for my National … Continue reading
Posted in Electronics, Resources, Test Equipment
Tagged gpib, hp 3585a, hpib, keysight screen capture, screenshot, spectrum analyzer
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Accuphase C-200 Professional Pre-Amp Full Overhaul
When Kenwood’s engineers left to form Kensonic, they really brought their A-game, and this Accuphase C-200 pre-amp is no exception. It’s a mammoth device, built with exceptional attention to detail and top of the line components throughout. The owner reported … Continue reading
Harmony H400 Tube Guitar Amplifier Repair
I recently had another Harmony amplifier, the H400, through the shop for an overhaul. It’s owner, who previously sent me a Harmony H500 for service as well, took it to a local tech but wasn’t satisfied with the repair so … Continue reading
Telefunken Bajazzo Sport 201 Transistor Radio
I don’t typically service portable transistor radios, but I make an occasional exception for something especially unique or interesting. The Telefunken Bajazzo Sport 201 is no exception – it’s a high end piece of German engineering, a great performer with … Continue reading
Posted in Electronics, Projects, Radio, Vintage
Tagged 201, bajazzo, bajazzo sport, portable radio, Telefunken, transistor radio
8 Comments
Sony TA-5650 Full Re-Cap and Adjustment
I recently got to work on another of the Sony VFET line of integrated amplifiers, the Sony TA-5650. I’ve had one through the shop previously, and this one came in for the same service. It came in running fine – … Continue reading
Fun with the HP 3585A Spectrum Analyzer
I spent some time playing around with one of my HP 3585A spectrum analyzers over the weekend to get a feel for its capabilities. While it’s only good from 20 Hz – 40 MHz, it’s a very capable tool within … Continue reading
Posted in Electronics, Gadgets, Test Equipment
Tagged 3585a, HP, LogiMetrics, spectrum analyzer
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1960 Grundig SO191 Stereo Hi-Fi Console Repair
This stunning piece of late mid-century modern German engineering, the iconic Grundig SO 191, recently came through the shop. It’s owner picked it up from an antique shop in nearly pristine cosmetic condition, but with a few electrical issues to … Continue reading
Posted in Audio, Hi-Fi, Projects, Vintage
Tagged german radio, Grundig, hi-fi, so 191, stereo console, vintage radio
28 Comments
Bose® 901 Series VI Active Equalizer #199732 Repaired
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 Active Equalizer, Bose, Bose 901, capacitor, capacitor replacement, vintage
1 Comment