Author Archives: retrovoltage

Would you look at that!

Posted on August 9, 2016 by retrovoltage

It’s pretty, but this 12BA6 tube has amplified for the last time. Vacuum failure has led to a gas intruding into the vacuum, and it makes a great light show when it’s being tested! As cool as it looks, this would cause … Continue reading →

Posted in Photos, Radios and Tubes, Vintage | Tagged , , , | 1 Comment

Bad Caps in Everything

Posted on July 20, 2016 by retrovoltage

I just had a bit of a scare with my Audio Precision analyzer. The 2004-era Dell OptiPlex GX270 which drives the AP hardware decided it would refuse to power up – just flashing the “ON” light for a fraction of … Continue reading →

Posted in Computers, DIY, Electronics, Test Equipment | Tagged , , , , | 3 Comments

DBX SFX-10

Posted on May 31, 2016 by retrovoltage

I saw this interesting set of speakers on Craigslist, but they sold quickly before I could investigate. They’re the DBX SFX-10s. There’s a very interesting article about their design in the May 1990 issue of The BAS Speaker, the publication … Continue reading →

Posted in Audio, Electronics | 6 Comments

Bose® Active Equalizer Test Platform

Posted on April 13, 2016 by retrovoltage

This project is going to take a while since I’m slammed in the shop, but I’m in the process of converting a Bose® 901 Series I Active Equalizer to  a test platform. With sockets for the transistors, and clip connections … Continue reading →

Posted in Audio, Bose, DIY, Electronics, Stereo, Test Equipment | Tagged , , , , , | 3 Comments

“Won’t that ruin the vintage sound?”

Posted on March 16, 2016 by retrovoltage

Audio as a hobby sits in an interesting place in the world. There are hard numbers and objective measurements made with lab equipment on one end, and on the other end you have the subjective and variable linguistic descriptions assigned … Continue reading →

Posted in Audio, Commentary, Electronics, Hi-Fi, Vintage | Tagged , , , , , , , | 3 Comments

Neat Little 60FX5 Stereo Single-Ended Tube Amplifier

Posted on March 6, 2016 by retrovoltage

While digging around, I came across a really simple circuit in the RCA Receiving Tube Manual describing a 1WPC stereo amplifier using only two tubes, the 60FX5 power pentodes, and a single silicon diode. The 60FX5s have high enough gain … Continue reading →

Posted in Audio, DIY, Projects, Stereo | Tagged , , , , , | 5 Comments

The Speaker Spotter – March 3rd, 2016

Posted on March 3, 2016 by retrovoltage

Some interesting stuff on Craigslist in this week’s The Speaker Spotter, a curated selection of Seattle’s local speakers for sale online. As always, Retrovoltage is not affiliated with any of these sellers and you should click through the link to the … Continue reading →

Posted in Audio, Collections, Speakers, Stereo | Tagged , , , , , , , , , | Leave a comment

New Bench Storage

Posted on February 26, 2016 by retrovoltage

Some pegboards, and wall mounting some parts bins, really cleaned up the benchtop!

Posted in Commentary, Photos | Tagged , , | 2 Comments

555 timer teardown (and a Retrovoltage drum trigger project)

Posted on February 23, 2016 by retrovoltage

Ken Shirriff’s blog has a fantastic and detailed teardown of a 555 timer, the ubiquitous decades-old timer circuit that turns up in so many places: If you’ve played around with electronic circuits, you probably know the 555 timer integrated circuit, … Continue reading →

Posted in Collections, Commentary, DIY, Gadgets | Tagged , , , , , , | 1 Comment

Antique Radio Shop near Kunming, Yunan, China

Posted on February 22, 2016 by retrovoltage

My friends over at Crimson Lotus Tea sent me this photo of an antique radio shop near Kunming, Yunan in China they ran into during a recent trip. They’re stacked to the ceiling in the shadows. Looks like a fun … Continue reading →

Posted in Collections, Photos | Tagged , , , , | 2 Comments