Varistor Characteristics for Magnatone Vibrato Circuits

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Willabe
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Re: Varistor Characteristics for Magnatone Vibrato Circuits

Post by Willabe »

Oh and Thank You to Stephen Keller for a great web site!!!!!!!

Brad :D
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Kagliostro
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Re: Varistor Characteristics for Magnatone Vibrato Circuits

Post by Kagliostro »

Many Thanks Trobbins

That's a GREAT idea [img:25:28]http://www.diyitalia.eu/forum/images/sm ... ns-489.gif[/img]

Ciao

Franco
Willabe
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Re: Varistor Characteristics for Magnatone Vibrato Circuits

Post by Willabe »

For a base line of Maggie vibrato, Lonnie Mack Wham, about 1/2 of this album has the Maggie vibrato on it.

http://youtu.be/OAH-G_aXHqY


Brad
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martin manning
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Re: Varistor Characteristics for Magnatone Vibrato Circuits

Post by martin manning »

I've posted a revision to the original document at the top of this thread that includes the final design of the MOV substitute for SiC varistors. It has also been posted at the Magnatone-Valco Yahoo Group site.

The MOV substitute seems to have solved the clicking that was observed in two trials (Jeremy's and ubxf's) using original Zener diode version which had back-to-back Zeners. Tim Robbins also tested a Zener version and did not get the clicking, but Tim's used only reverse biased Zeners. I'm now wondering if the forward biased Zener was the source of the clicking. Something else to test, perhaps.

Thanks for the link to the Lonnie Mack recording, Brad!
Willabe
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Re: Varistor Characteristics for Magnatone Vibrato Circuits

Post by Willabe »

Your welcome.

I like that album a lot. He could really play and was a good singer too.

It was made up of singles he had released before and they just put them out as an album.

Those singles were cut before John Mayall's Blues breaker album with Clapton. Lonnie was layin down fast guitar leads (that said something, not just see how fast I can play) before any of the white blues/rock guys.

SRV said 'Wham' was the 1st single he ever bought.

Brad :D
dinkotom
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Re: Varistor Characteristics for Magnatone Vibrato Circuits

Post by dinkotom »

Willabe
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Re: Varistor Characteristics for Magnatone Vibrato Circuits

Post by Willabe »

Yes, Lonnie knew Ward and heard him playing through a Maggie and liked it so much he bought his own Maggie, so goes the story.

Thanks for posting those links!


Brad :D
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trobbins
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Re: Varistor Characteristics for Magnatone Vibrato Circuits

Post by trobbins »

With thanks to Stephen Keller and Martin Manning for editorial direction, I've collated some brief details on the Maggie vibrato technique in a pdf'd doc
http://dalmura.com.au/projects/Magnaton ... design.pdf

The doc is meant to be 'work in progress', as I will try and update it as more details come to light - whether that be other relevant historical details, or better clones, or general comments on clones such as Martin's MOV clone as more people try it. The details may be in error, or not too clear, so I'm happy to modify. If it is modified it will have a later date in the header. I already have an update to add to an unknown appendix reference that Stephen found.

Ciao, Tim
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martin manning
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Re: Varistor Characteristics for Magnatone Vibrato Circuits

Post by martin manning »

Your write-up turned out very nicely, Tim.
Diablo1
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Re: Varistor Characteristics for Magnatone Vibrato Circuits

Post by Diablo1 »

Thanks very much Tim for spending the time to compile all this information. This will make a great addition to my "Magnatone File".
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didit
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Re: Varistor Characteristics for Magnatone Vibrato Circuits

Post by didit »

Yep. Nicely done. I've forwarded it to a few people and filed it too.

Thanks .. Ian
Last edited by didit on Fri Feb 26, 2021 3:47 pm, edited 1 time in total.
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trobbins
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Re: Varistor Characteristics for Magnatone Vibrato Circuits

Post by trobbins »

trobbins wrote: brief details on the Maggie vibrato technique in a pdf'd doc
http://dalmura.com.au/projects/Magnaton ... design.pdf

The doc is meant to be 'work in progress', as I will try and update it as more details come to light
I've just uploaded an update of the linked doc - main addition is information related to Schober organ use of varistors in their vibrato.

Doc is dated 21 May - if not then refresh cache (Ctrl-F5 in IE).

Ciao, Tim
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Kagliostro
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Re: Varistor Characteristics for Magnatone Vibrato Circuits

Post by Kagliostro »

Many Thanks Tim

Image

Ciao

Franco
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