Category Archives: Electronics

1954 Philips 778-2 Canadian Antique Radio Repair

Posted on October 24, 2013 by retrovoltage

I was lucky enough to get to work on a beautiful 1954 Philips 778-2 radio console. It had been moved around and played for a while but eventually ended up giving only buzzing instead of audio output. I’m surprised it … Continue reading →

Posted in Electronics, Projects, Radios and Tubes, Vintage | Tagged , , , , , , , , , , , , , , | 16 Comments

Evidence of Past Repairs

Posted on September 16, 2013 by retrovoltage

It’s always interesting to see what’s happened with equipment that’s been worked on previously. It’s often a mixed bag with some great repair jobs, some that have a lot of room for improvement, and some that really just don’t measure … Continue reading →

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

KN0CK HF Converter Rev. 4 is Released!

Posted on July 25, 2013 by retrovoltage

The complete Rev 3 KN0CK HF Converter has sold out and been discontinued. That’s okay, though, because it’s been replaced with the KN0CK RTLSDR for HF Revision 4! This model incorporates a lot of the feedback from the community about the … Continue reading →

Posted in DIY, Electronics, Gadgets, Radio, Technology | Tagged , , , , , , , , , , , , , | 1 Comment

Overloaded 1931 Transformer [Fried Electronics]

Posted on June 7, 2013 by retrovoltage

I’m working on a 1930/31 Westinghouse WR-8 Columnaire clock-radio which had a bad transformer. The filter capacitors failed and shorted the high-voltage secondary, burning it open and causing a lot of heat and melting.   The replacement is a General … Continue reading →

Posted in DIY, Electronics, Projects, Radio, Vintage | Tagged , , , , , , , , | 3 Comments

Coming Soon: KN0CK Rev B Integrated HF RTLSDR

Posted on May 1, 2013 by retrovoltage

Marty KN0CK developed a very interesting v1.0 HF converter based on surface mount technology that fits inside the casing of an RTLSDR tuner dongle. He’s recently sent me schematics for the revision, which should offer even better performance! This new iteration … Continue reading →

Posted in Electronics, Projects, Radio | Tagged , , , , , , , , , , , , , , , , , , , , , , | 7 Comments

KN0CK HF Upconverter Fits Inside the USB Tuner’s Enclosure

Posted on February 19, 2013 by retrovoltage

Marty KN0CK sent me some details to publish about his great looking miniature HF upconverter board for the RTLSDR, the HF Alchemy DVB-T Active HF Upconverter. It’s an incredibly miniature SMT board with an SA612 mixer and SMT oscillator, and … Continue reading →

Posted in DIY, Electronics, Photos, Projects, Radio | Tagged , , , , , , , , , , , , | 11 Comments

Thrift Store Jamo MPA-101 Repair

Posted on February 11, 2013 by retrovoltage

I started working on a Jamo MPA-101 amplifier back in August for a friend and after some early work it sat for a while. He’s re-doing his audio system at home so I spent a few hours to finish troubleshooting … Continue reading →

Posted in DIY, Electronics, Projects, Speakers | Tagged , , , , , , , , , , , , , , , , , , , | 12 Comments

Bad Capacitors Strike Again

Posted on February 5, 2013 by retrovoltage

I’m working on another Bose 901 Series 1 equalizer. It looks to be the same manufacturing run as the first one I wrote up last July, uses the same components, and those components look like they’ve had the same failure … Continue reading →

Posted in Electronics, Hardware | Tagged , , , , , , , | 9 Comments

DIY SDR HF Up-Converter by WA7JHZ: Another good choice for your RTLSDR.

Posted on February 2, 2013 by retrovoltage

Reader David Forsman, WA7JHZ, read the round-up of RTLSDR upconverter choices and sent me a photo and build schematic of one he designed which was featured in the January 2013 issue of QST, the ARRL‘s monthly magazine. This circuit up-converts … Continue reading →

Posted in DIY, Electronics, Projects, Radio | Tagged , , , , , , , | 2 Comments

First Look: 1934 Grunow 750 World Cruiser

Posted on November 19, 2012 by retrovoltage

I picked up this Grunow 750 “World Cruiser” radio from eBay a little while ago for an incredible deal and now it’s time for it’s turn on the bench. These radios are fairly uncommon and frequently sell for several hundred … Continue reading →

Posted in Electronics, Projects, Radios and Tubes, Vintage | Tagged , , , , , , , , , , , , | 3 Comments