Clough-Brengle Model 79-B Beat Frequency Oscillator

I acquired a few pieces of pre-war Clough-Brengle test equipment as part of a deal for a Tek 454A oscilloscope. 

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This is one of them, the Clough-Brengle Model 79-B Beat Frequency Oscillator.

I had originally learned about Clough-Brengle from Ron Lawrence’s posts on the Antique Radio Forum, which led to his Clough-Brengle history and photos web pages. There is some info on other sites, too: 

Alan Douglas’s book Tube Testers and Classic Electronic Test Gear also has a few photos of Clough-Brengle equipment: their 282-A sweeping audio oscillator, and their ZM-11 impedance bridge.

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The old Clough-Brengle gear is beautifully constructed. I never restored them as I was reluctant to put in the effort for the high-quality restoration they deserved. I kept them as shelf queens for a while, then eventually sold them to an MIT student at one of the MIT Fleas. 

I did take a number of photos first, though. Looking through them makes me wish I had held on to the gear. One has to draw the line somewhere, I suppose.

I thought others might be interested in the photos, so here they are. I hope you enjoy them.

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The eye tube is to calibrate the Beat Frequency Oscillator against the line frequency.

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Looks like some mud-daubers had a home here at one time.

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© Steve Byan 2011-2019