Antique Electronics and Vintage Solid State

I collect and restore antique vacuum tube electronics (i.e. "boatanchors") and vintage solid-state gear. I’m mostly interested in post-war test equipment, communication receivers, and consumer radios.


This page only has the most recent posts, but you can view a full index of my posts to Antique Electronics and Vintage Solid State.

RCA WV-98C Senior VoltOhmyst VTVM Restoration

I have a batch of three RCA WV-98C VTVMs on my bench for restoration.

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They aren’t the easiest VTVMs to work on. The three meters are from three different production runs: K114, K117, and L60.

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I started by removing the meter and the front panel.

HP 456A AC Current Probe

I wanted a simple project to take a break from working on my RCA WV-98C VTVMs. I’ve had a Hewlett Packard 456A AC Current Probe sitting around for a while. 


The 456A is a clip-on AC current probe. It is comprised of a clip-on probe and a current-to-voltage amplifier and converter. …

Technology Instrument Corp Knob

I acquired a General Radio 1432-K decade resistance unit that was missing one of its General Radio knobs. 

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It had been replaced by this unique oddity - a knob made by Technology Instrument Corp (TIC). …

Centralab Rotary Switches

I needed to describe an unusual connection to a rotary switch in my Triplett 850.

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I remembered that I had a scan of this old Centralab Assembly Instructions for 1400 and 2500 Series Rotary Switches. It has this handy diagram that names many of the parts of these rotary switches.

Triplett 850 VTVM Restoration

I’ve started restoring my Triplett 850 VTVM

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The Triplett 850 Type 2 manual is available in my Liberated Manuals section. Didier (KO4BB) also has an excellent scan of a somewhat newer manual in his repository, along with an

Reproduction battery for General Radio 1232-A Tuned Amplifier and Null Detector

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The General Radio 1232-A Tuned Amplifier and Null Detector was primarily intended for use as a detector for bridges. It is a low-noise amplifier and a filter that can be tuned from 20 Hz to 20 kHz, or set to 50 kHz, 100 kHz, or a flat frequency response.

60 Hz Filter for the HP 6920B

The HP 6920B Meter Calibrator uses the waveform of the input AC power to derive the waveform of its calibrated AC output. The HP 6920B controls the average value of the output AC. Consequently, if there is much distortion on the power line, there will be a difference between the RMS and average value of the meter calibrator AC output. 

Waveforms, Inc

Over on the Antique Radio Forum, a denizen of the forum going by the monicker “Bonzo” posted some new information about Waveforms, Inc

UREI Waveforms acquisition

Bonzo posted the October 1967 issue of the United and Affiliates (aka United Recording Electronics Industries) Newsletter

Heathkit HM-10-A Tunnel Dipper

Over on the Antique Radio Forum, there’s a gathering of grid-dip oscillators.

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One of my contributions was this Heathkit HD-10-A Tunnel Dipper.

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It uses a tunnel diode as the active device in the oscillator.

Heathkit GD-1250 high frequency coil

Over on the Antique Radio Forum, Steve “azenithnut” mentioned he was missing the high frequency coil for his Heathkit GD-1250 Grid Dip Oscillator.

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His GD-1250 is missing this coil. I thought I’d post some photos of the coil from my GD-1250. …

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© Steve Byan 2011-2019