Who Invented Moving Coil and Moving Magnet? - Klaus R

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JaS
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Who Invented Moving Coil and Moving Magnet? - Klaus R

Post by JaS » 14 Jan 2011 21:48

Download

Many thanks to Klaus R

Blue Angel
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Re: Who Invented Moving Coil and Moving Magnet? - Klaus R

Post by Blue Angel » 15 Jan 2011 09:15

JaS wrote:Download

Many thanks to Klaus R
Ditto.

ba

Terry Robinson
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Who Invented Moving Coil and Moving Magnet - Klaus R

Post by Terry Robinson » 17 Jan 2011 00:28

A truly excellent article, but don't forget Paul Voigt.

Cheers,

Terry.

Klaus R.
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Post by Klaus R. » 18 Jan 2011 09:03

Paul Voigt, did he design phono cartridges or only transducers for loudspeakers?

Klaus

Bebé Tonto

Post by Bebé Tonto » 18 Jan 2011 16:50

Klaus, great article. Now you owe us the Part II, covering "modern" (1958-) designs...

Terry Robinson
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Who invented Moving Coil and Moving Magnet? - Klaus R

Post by Terry Robinson » 19 Jan 2011 04:55

Hello, Mr Klaus:

According to the chapter "The life and achievements of P. G. A. H. Voigt", part of the book "Sound Bites: 50 Years of Hi-Fi news", Mr. Voigt invented both a Moving-Coil disc cutter and a Moving-Coil pickup (cartridge). This pickup was not patented and was much copied: Leak was one.

Cheers,

Terry.

RED_One
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Re: Who Invented Moving Coil and Moving Magnet? - Klaus R

Post by RED_One » 23 Nov 2011 03:01

We should not forget the contribution made by A R Sugden (Connoisseur) to stereo playback.

spittenkittens
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Re: Who Invented Moving Coil and Moving Magnet? - Klaus R

Post by spittenkittens » 22 Dec 2014 20:47

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spittenkittens
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Re: Who Invented Moving Coil and Moving Magnet? - Klaus R

Post by spittenkittens » 22 Dec 2014 20:51

I messed up, these is a mm cartridge from an early 78 player. The motor is "spin to start" It was supposed to hook up to a radio amp. The magnet is the huge "U" shaped magnet. The arm vtf is probably a pound and took steel needles. It is not working right and I suspect the magnet has lost it's power. There was corrosion on the copper wire leads but I was able to clean that up.
Anyway you can tell it takes years of experience to to where we are today.

circularvibes
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Re: Who Invented Moving Coil and Moving Magnet? - Klaus R

Post by circularvibes » 22 Dec 2014 21:10

Thanks for the neat pics Spittenkittens. It was a common repair to antique electric phonos to have their cartridges remagnetised. A warning too, they could be demagnetised by dropping them sharply on the record/motorboard. I have never heard one and would like to know if they are pleasant to hear. I wonder if modern MC carts can be demagnetied too. I suspect not as they probably use better magnets nowadays.

spittenkittens
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Re: Who Invented Moving Coil and Moving Magnet? - Klaus R

Post by spittenkittens » 22 Dec 2014 22:08

It is from a rca r-93-a. I did not have any contact cleaner when I was messing with it awhile back. I was getting moving on a vom (ohms) so maybe it does work now. I had tried to re-magnetize the horseshoe magnet with another powerful magnet.
I need to find something to amplify the signal, but I am not in the mood to mess with it right now. Would be fun if it works. The motor is only 7 watts. The early days of electricity were interesting. I think they understood more than technology would allow them to do at that age, at least to mass produce.

circularvibes
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Re: Who Invented Moving Coil and Moving Magnet? - Klaus R

Post by circularvibes » 23 Dec 2014 07:39

Beware, the motor MIGHT be old enough to be a 25 cycle one. If it is, you will burn it out if you try running it on today's 60 cycle current. As to amplifying it, you will need a matching radio, I don't believe there would be the right curve or input voltage on any of today's amps. This just means you get to go shopping for another antique for your collection(and maybe restore it too). I know here in Canada that 25 cycles was used in some areas until the 1940's. Our hydro companies had to repair or replace anything that didn't conform to the 60 cycle standard by legislation, or they wouldn't have been allowed to change the grid. I know of this because family friends had a clock that was a wedding present that hasn't been able to be plugged in because a new motor wasn't available and they didn't want to give it up as it was also a silver floor lamp.

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