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This looks like one of the early 30's RCA Victor Electrolas with a home recording function using pre-grooved discs. I suspect there's a speak-o-phone aluminum disc with it, or else that's what the owner used. Anyhow this must have been a VERY expensive piece when new but it looks like it had a hard life since.
http://syracuse.craigslist.org/atq/1432956859.html

This machine is later than the 1932 vintage RCAs that used the silent groove little vinyl recording blanks. The earlier system embossed the silent groove with a blunt recording stylus tracing the groove rather than cutting a groove. This is the later type, circa 1940 that used nitrocellulose recording blanks. It cuts the groove with a sharp recording stylus. The recording arm is moved across the disc via a feedscrew arrangement located under the deck.

It's pretty amazing that something like that is available so cheap, even though it's had a hard life. It must have been very expensive new and is technically very interesting.

gregbogantz wrote:This machine is later than the 1932 vintage RCAs that used the silent groove little vinyl recording blanks. The earlier system embossed the silent groove with a blunt recording stylus tracing the groove rather than cutting a groove. This is the later type, circa 1940 that used nitrocellulose recording blanks. It cuts the groove with a sharp recording stylus. The recording arm is moved across the disc via a feedscrew arrangement located under the deck.

Sounds interesting- in theory you could still cut acetates on this, though it would probably cost a small fortune to rebuild.

These home recorders that used acetate blanks (several manufacturers made them) from around 1940 never worked very well. They employed crystal piezo elements in the recorder and cut with a cold stylus. The result was pretty noisy and lo-fi. Today, the crystals are nonfunctional and would have to be rebuilt. One or two services are available to do this, but you would still wind up with a machine capable of only its original poor performance. Wire recorders quickly took over as the home recording device of choice until after we appropriated the magnetic tape technology from the Germans after WWII. Wire recorders were capable of much better fidelity and lower noise than these disc recorders as a consumer product. Of course, they had their own problems (bird's nest wire tangles, anyone?), and home recording never really got off the ground until the introduction of magnetic tape after WWII.

That doesn't surprise me- cost a fortune and the results probably were no better than a Wilcox-Gay. It's a shame to see it in such rough condition though.

Someone on AudioKarma found this arm in a box with miscellaneous items from an estate sale recently:

That RCA tonearm is known as the "inertia" arm. For a reason: The wide flare at the front end holds additional mass that is designed to reduce the tonearm resonance frequency and improve bass performance. The additional mass at the front was counterbalanced by more mass at the tail so that the tracking force remained about the same as earlier designs - around 160 grams. Occasionally you'll see the "professional" version of this arm which was designed for transcription record playback. It has an even MORE massive flare and weights added to the front and back. These tonearms were fitted with the early horseshoe magnetic pickups and were widely used by RCA (and OEM'd to other makers) from around 1931 to '35 or so when the early crystal cartridges came into popularity.