The Talking Machine Forum — For All Antique Phonographs & Recordings

I have been restoring a Kalamzoo Duplex recently and have a few questions to help complete the job.

1. The machine came with a spring on the support arm, I believe this was intended to adjust the weight on the soundbox but it cannot be seen on most photos of complete machines as it would be hidden by the horns. Does anyone have a photo showing the arrangement of the missing part(s) that the other end of the spring should attach to? It looks like it would fit through the two holes in the horn support bracket and tie rod.

2. There is a hole in the horn support bracket pivot which looks like it might have been intended to take a retaining screw but it does not appear to be tapped, what was this intended for?

3. How were the original elbows fixed to the soundbox to stop it rotating under the weight of the horns in use?

The coil spring on the support arm was originally attached to a small post which occupied the hole on the pivot. (The coil spring pictured looks a bit too long.) Victor was assailing the company in court for violating Claim 5 of U.S. patent #534543, which covered any talking machine whose needle was driven by the groove of the record. Late-production Duplexes like this one were equipped with a coil spring in an attempt to circumvent that patent. The idea was that the coil spring would exert clockwise tension on the pivot, which would in effect drive the needle toward the center of the record - even without the groove's help. As a matter of fact, Hawthorne & Sheble tried a similar gambit with its Star machines, claiming that such spring-loaded pressure caused the groove to inhibit (rather than propel) the needle across the record surface. It didn't work for either company.

Below is a photo of the complete gadget in place.

George P.

George,

Thank you for the response, I did not think of that possibility. Do you know how long this post was and if these late models still had the weight adjuster on the horns?

Regards

John

John,

I'm sorry, but I didn't measure that post when the picture was taken. Hopefully the image will help you make the length passably close.

As for the weight adjuster, I have no recollection as the picture was taken 19 years ago. I'm sorry I cannot offer additional details.

George P.

George,

Thank you for the confirmation, I had missed the photo when I looked through my copy. It is sobering to realise two decades have passed since these superb books were published.

I saw a photo of reproduction parts for the weight adjuster some years ago but I cannot recall ever seeing one set up on a machine hence I wondered if any Duplex owners on the forum have a genuine example they could illustrate.

Regards

John

FDL1990 wrote: Thu Jan 28, 2021 2:32 pm It is sobering to realise two decades have passed since these superb books were published.

Indeed it is! The Compendium was published 24 years ago...

George P.