This modern take on the tube tester is a must-have for anyone who regularly works with tube-type electronics.
The C22 — one of my holy grail audio electronics acquisitions — is known for quality in engineering and construction and audiophile performance. The C22, which originally sold for $330 in 1965, now sells for between $3,000 and $6,000, depending on condition. Even if you don’t own a C22, by following along, you can pick up pointers for your own vintage restoration project — especially when it comes to restoring improperly serviced gear.
Every restoration — even repeat restorations of the same model — reveals something new about tubes and tube circuitry. In this restoration of the Jubilate, the focus is on reclaiming a circuit board covered with dirt, converting a selenium power supply to one based on silicon diodes, and the best ways to rejuvenate the cosmetics of your radio, including how to refinish a wooden cabinet.
Teardowns of vintage gear in which you carefully note component values, construction techniques, and create a schematic from scratch are a great introduction to vacuum tubes. The next level (and the focus of this article) is to restore tube-type devices, starting with a tabletop radio. Not only will you learn to work with the technology, but you’ll have something of value when you’re done.
It took me eight months of part-time work to restore all 168 pounds of a Heathkit “H-1.” I would like to share a few of the trials and tribulations I went through to resurrect this beast.
Magnetic loop antennas are becoming popular today because they can be very efficient for their size, do not need radials (even though most designs are vertically polarized), have useful takeoff angles, and can be easily rotated to peak or null a signal. Here’s how I designed a convenient setup for myself.
In mid 2012, I noticed an amplifier on eBay that was out of a 1952 Rock-ola 1436 jukebox, and just had to have it. It was essentially a dead carcass, so I decided to restore the amplifier and make it able to stand alone. I wanted to make the restored amplifier as authentic as possible to the 1952 version.