any body know the pin out of the old whites coils?

Hello everyone, My buddy got an old (vacuum tube) whites gold master from a storage unit he purchased. After some tinkering I was able to bring it back to life. My conundrum now is that it has a 3" coil on it. It could only detect my ring from about 3" away. I would like to wind a new larger coil but cant find any pin out for connecting to the detector. it has 4 pins. I get conductivity from 1,2,3 but 4 seems to be open. So what type of coil was standard on these machines? I was assuming it would be a dual concentric, but my understanding was that each coil would be connected to two pins? Any help you can send my way would be appreciated.

Caleb

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I couldnt find one on it, the closest manual I could find was the 66s. I looked through all the old gold master manuals and was unable to find an identical picture. There also is no model number or serial number on it I could find. will put up some pics in a minute.

Posted on: November 22, 2011, 09:01:08 PM

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Ok here are the pictures






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would z be impedance? and does it only use a single coil?

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I was able to modify the 9v and 1.5v I had to tape and solder together a bunch for the 67.5v. If we decide to keep it I think I will build a 12v supply with voltage regs for the 1.5 and 9 and a step up transformer for the 67.5.
So if it only has a single coil what is pin 3 tied to? is the coil half tapped? and is pin 4 for a shield or is it unconnected?

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So then is pin 3 a half tap on the main coil? Sorry if I am being obtuse. I was hoping to try out a DD coil, but it doesn't appear that one will work for this model.
edit>
I get a reading of 11.5 ohms from 1-2, 11.8 ohms from 2-3 and 15.5 ohms from 1-3. I will have to set up a different meter for the impedance readings. I was curious did they pot chokes or caps into the coil? trying to account for the difference in readings as if it was simply a half tap 1-3 should be about 23 ohms instead of 15.5. When I get this all figured out I will post a how to, as I was unable to locate much info on the web.

Thanks for the help

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