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. 

IMG 4274.jpg

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.

IMG 4295.jpg

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.

IMG 4275.jpg


IMG 4276.jpg


IMG 4277.jpg


IMG 4278.jpg


IMG 4279.jpg

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

IMG 4280.jpg


IMG 4283.jpg


IMG 4284.jpg


IMG 4285.jpg


IMG 4286.jpg


IMG 4287.jpg


IMG 4288.jpg


IMG 4289.jpg


IMG 4290.jpg


IMG 4291.jpg


IMG 4292.jpg


IMG 4293.jpg


IMG 4294.jpg

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

IMG 4296.jpg


IMG 4297.jpg


IMG 4298.jpg


IMG 4299.jpg


IMG 4300.jpg



© Steve Byan 2011-2016