The DIY Musician: Build Your Own One-Tube Amplifier — Vintage Plans from 1954

Last week, I shared two sets of vintage DIY plans for an electric guitar and a tube-driven “throbbing” vibrato.

This week, I’ve discovered another treasure from the Eisenhower era—a one-tube amplifier that uses a 117L7/M7GT tube.

I’ve taken the original scans of the plans and turned them into an archived PDF with enlarged photos from the article. Download the plans at

The plans suggest the amp would be good for amplifying a phonograph player or radio. However, swapping out the phono jack for a mono 1/4” guitar jack should suffice.

WARNING: I should note that working with tubes and transformers is dangerous and these plans are offered as an archived curiosity. If you’re not skilled at this stuff, I suggest starting with a simple solid-state cigar box amp kit, such as the Gitty 2.5-watt amp kit. I’ve made a bunch and even documented my insane mods, which include Ed Wood-style antennas, Jello mold speaker horns and other found objects.

I offer the same invitation as last week with the guitar and vibrato plans: If you build the amp from these vintage plans, send me pics, videos and descriptions so I can write a followup column. My email is

Shane Speal is "King of the Cigar Box Guitar" and the creator of the modern cigar box guitar movement. Hear the music, see the instruments and read about his Cigar Box Guitar Museum at Speal's latest album, Holler! is on C. B. Gitty Records.