I just added another DD machine to my collection! an IU-19!

[marcapra]

Fran, do you know when the 10"/12" keys were invented and first put into machines?

[Lucius1958]

Fran, do you know when the 10"/12" keys were invented and first put into machines?

If I may add my observation: I have an early BC34 (with the #100 horn, so probably Apr/May 1922), which has its original 10"/12" buttons...

Bill

[fran604g]

Fran, do you know when the 10"/12" keys were invented and first put into machines?

I don't know when they were invented, but I agree with Bill that they were introduced in 1922. I have a hunch the accessory may have been developed much earlier.

I have a patent search on my long todo list...

Best,
Fran

[fran604g]

Fran, do you know when the 10"/12" keys were invented and first put into machines?

I don't know when they were invented, but I agree with Bill that they were introduced in 1922. I have a hunch the accessory may have been developed much earlier.

I have a patent search on my long todo list...

Best,
Fran

I did a patent search using a couple of dozen keywords and phrases, for several hours, and had no success locating anything similar to this device ever being held in patent by Edison (as assignee). It occurs to me that this was probably NOT a patentable invention; distilled down to its essence, it's really only a modified rotary indexing device.

Best,
Fran