Category Archives: Resources

Everything to Know about Bose 901 Series I and Series II Active Equalizer Repair & Speaker Systems (and the 800, too!)

Posted on June 12, 2026 by retrovoltage

A deep dive into the tips and tricks for repairing the Bose 901 Series I and II, plus the Bose 800 Series I and II, along with a discussion of their history and variations, sourced from direct experience repairing more than 500 examples. Includes schematics and parts lists. Continue reading →

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Antenna Distribution for AM Radios

Posted on October 24, 2015 by retrovoltage

I’ve had a few questions come my way about antenna distribution systems for AM radios, specifically to connect something like a large attic antenna to multiple radios at once. There’s a lot out there designed for VHF/UHF or CATV signals, … Continue reading →

Posted in DIY, Electronics, Gadgets, Radio, Resources | Tagged , , , , , , , , | 9 Comments

Extracting Screenshots from the HP 3585A Spectrum Analyzer

Posted on April 22, 2015 by retrovoltage

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 →

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How Speakers Make Sound

Posted on December 3, 2014 by retrovoltage

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

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Getting Started With Vintage Radio and Electronics: Basic Tools for the Hobbyist

Posted on September 18, 2014 by retrovoltage

This page is outdated, but I’m keeping it up for SEO reasons. Here’s the current version:

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Parts of a Vintage Radio – Middle Tube Era

Posted on September 8, 2014 by retrovoltage

Photos with parts diagrams of a vintage tube radio – the Crosley 10-139, from about the middle of the tube era. Click each photo for full size.  

Posted in Commentary, Photos, Radios and Tubes, Resources, Vintage | Tagged , , , , , , , , , , , , , | 3 Comments