Voodoo Main Discussion

[MartyJ1963]

Thanks George. I think I came across some Van Damme 4-Core screened microphone cable (6mm) that I may purchase. Thanks again. Marty.

[godigit1]

Thanks George. I think I came across some Van Damme 4-Core screened microphone cable (6mm) that I may purchase. Thanks again. Marty.

Be careful when using microphone cables. the ones ive used have a two layer insulation at least it looks that way.
The outer layer is black and is a conductive plastic of some type. I think its part of the shielding of the cable.
as long as its away from your solder joint Ive had no problems.
I've been meaning to check if it was connected to ground in the mic connector.

[MartyJ1963]

@Godigit,,,Thanks for the tip! Regards, Marty.

[godigit1]

I don't think you could have a dual-field coil that has a concentric RX loop. At least I've never seen one.

Hi Qiaozhi,
Been thinking about the dual field thing and wondering if you thought this configuration could work?


Thinking that maybe we could get the benefits of a dual field in pi mode and give it a larger detection area and while in hybrid mode the possible benefits of a DD for separation of targets.

[Qiaozhi]

Hi Qiaozhi,
Been thinking about the dual field thing and wondering if you thought this configuration could work?
[ATTACH]53735[/ATTACH]

Thinking that maybe we could get the benefits of a dual field in pi mode and give it a larger detection area and while in hybrid mode the possible benefits of a DD for separation of targets.

It's a bit difficult to follow the wiring in your diagram. Can you make it a bit clearer?

[MartyJ1963]

Hi All,,,Found time between repairs to install STEP 1:-The Voodoo Power Supply and TP1,TP9,TP14, TP15 + PL9. STEP 2 will be The Transmitter Circuit. Regards, Marty.

[6666]

Hi Qiaozhi,
Been thinking about the dual field thing and wondering if you thought this configuration could work?
[ATTACH]53735[/ATTACH]

Thinking that maybe we could get the benefits of a dual field in pi mode and give it a larger detection area and while in hybrid mode the possible benefits of a DD for separation of targets.

Could you clarify the winding directions please

[godigit1]

It's a bit difficult to follow the wiring in your diagram. Can you make it a bit clearer?

Something like this. I was thinking wrapping the dual field part as you would normally except to a d style inner coil. The wraps of the inner coil could be played with a bit to get a lower transformation ratio between ds to act as a bucking coil I'm thinking and or that wont matter if it balances out like a regular DD the later preferred. the Rx DD of course would have to be phased properly.

I have enough coils around to do a experiment thinking might throw something together and see if I can get it to null.
No small DDs so I may go 12" outer round and 4" double OO for the DD portion since I have them.

Thanks again for All this .

[godigit1]

Could you clarify the winding directions please

Hi 6666,
I think I have to do some experimenting to see if this could work. It was mainly a thought experiment but I'm in coil mode and I cant stop thinking about it.

[Carl-NC]

Don't think it will ever balance.

[surfdetector]

Hi All,,,Found time between repairs to install STEP 1:-The Voodoo Power Supply and TP1,TP9,TP14, TP15 + PL9. STEP 2 will be The Transmitter Circuit. Regards, Marty.

Looks good Marty,
I will be starting mine on the weekend.

[Qiaozhi]

[ATTACH]53740[/ATTACH]

Something like this. I was thinking wrapping the dual field part as you would normally except to a d style inner coil. The wraps of the inner coil could be played with a bit to get a lower transformation ratio between ds to act as a bucking coil I'm thinking and or that wont matter if it balances out like a regular DD the later preferred. the Rx DD of course would have to be phased properly.

I have enough coils around to do a experiment thinking might throw something together and see if I can get it to null.
No small DDs so I may go 12" outer round and 4" double OO for the DD portion since I have them.

Thanks again for All this .

Don't think it will ever balance.

Carl beat me to it.
I really cannot see how that configuration would balance. Obviously the 2 DD loops will balance on their own, but then you've added a large TX loop around the outside that upsets everything.

[dbanner]

Don't think it will ever balance.

Correct

[godigit1]

That's Why I ask Thanks Guys It Was A thought. But I think it can be done as a 3 coil concentric. Maybe a 12" 8" and 4" for the rx, two outer coils as the dual fields damped as normal Rx coil bucked off inner dual field coil should work just like a concentric.
What do you guy think about that one.

[MartyJ1963]

Hi All,,,,STEP 2:- Transmitter Circuit complete. Next,,STEP 3:-Installing the LCD and Buttons,,,I first have to decide which enclosure I'm using and whereabouts on the Detector shaft it will sit so I can measure how much wire I need for the LCD and Buttons.
How can I test that the Transmitter circuit is functional please?Thanks, Regards, Marty.