Home Combination question

[gibsonj]

Hey folks

This past weekend, I picked up a Home Model B project machine. This is my first Home, so I'm still orienting myself to the design. It was advertised as a combination machine, but here's where I have questions.

It does have a Model O reproducer and horizontal carriage, with a Cygnet horn bracket attached to the rear. Looking at the left side of the upper belt pulley, I can see a planetary gear. But, there is no switch mechanism, nor any evidence there ever was. Checking the Frow book, there is mention there of Model B conversions not having a switch, but I'm not sure. I guess I fundamentally don't understand how the 2/4 mechanics were designed to work.

Can any of you straighten me out on this? Do I have a "partially" converted machine or am I just missing something?

Thanks.

John

[maroongem]

John,

Normally, your machine would have required a combination attachment that was offered by the Edison factory when the 4M Amberols debuted in 1908. This would have had a yoke that fit over the gear stanchion that had a switch that allowed you to change from 2-4M. This was done by an inner shift mechanism that fit inside the main pulley that the belt was attached to. Also, a mandrel was included with the kit as well as a Mod H Reproducer. The later Mod D & E had the same type of shift mechanism incorporated with the main pulley but you no longer had a switch, you simply pulled the shift mechanism in or out depending on which record duration you were playing.
If you only have the main drive pulley, I would think your machine is still only a 2M player.
I can supply pix of the different types if that would be a help.

Bill

[gibsonj]

Hey Bill

Thanks. Some pix would be great for reference if not too much trouble for you. Hope all is well.

John

[maroongem]

John,

Here a 2 pix of the different gear changing mechanisms found on a HOME Phonograph. The one depicted on the Mod. E is the same as found on the D. The Mod. F was 4M only.

Mod. B pulley & gear changing mechanism


Mod. E pulley & gear changing mechanism

[maroongem]

John,

Were the pix helpful?

[gibsonj]

Bill

Yes, very. Looking at my machine carefully, I am able to shift the feedscrew shaft left and right, and the smaller pulley as shown in your Mod. E picture is present, but does not mesh correctly (haven't taken it apart yet to investigate). So, I'm pretty convinced that I have a Mod. B machine without the gear changing switch present, or a Mod. B machine with the combination shaft common to Mod. D or E.

The Frow book mentions there were several variations of the combination attachment upgrades. Since my machine has the horizontal carriage, a Cygnet horn bracket installed, and the Mod O reproducer, I'm thinking this was a "field upgrade" to get the machine to 4-minute capability. I'm just wondering if the switch is indeed missing, or this was a "make it work" using available parts.

Thanks for all your help.

John

[maroongem]

Hi John,

That's an interesting marriage, a D or E 2/4M set-up applied to a Mod.B machine! Where you have an endgate, you will have to adjust both end bearings so that the small button held by a spring on the small diameter of the inner shift pulley can mesh with the groove cut in the shaft at the belt end.
My guess is that inner pulley is not pulling out far enough to allow for 4M play.
If your inner pulley has a lip on the end, it is most definitely for a Mod. D or E and the mechanics of how they all work is the same.

Bill

[gibsonj]

Hey Bill

I'll look at it closely again tonight. Thanks for the insight.

John